Oxnard Gem & Mineral Society, Oxnard Ca. August 2017...

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Page | 1 Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8 K. Kish OGMS Editor P.O. Box 246 Oxnard, Ca. 93032

Transcript of Oxnard Gem & Mineral Society, Oxnard Ca. August 2017...

Page 1: Oxnard Gem & Mineral Society, Oxnard Ca. August 2017 ...oxnardgem.com/content/newsletter/2017/2017_Aug_RockBag.pdfGEMS & MINERALS DEPARTMENT Superintendent – Diane Cook (805) 889-1209

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

K. Kish

OGMS Editor

P.O. Box 246 Oxnard, Ca.

93032

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

The Oxnard Gem & Mineral Society is a non-profit organization formed to increase our knowledge in geology,

mineralogy and other such related fields in the earth sciences. We classify, cut, grind and polish rocks and minerals for

our personal collections and to display at club shows. We learn from each other through club speakers, programs and

monthly fieldtrips. We co-operate with other clubs to encourage others to participate in our activity.

The Oxnard Gem & Mineral Society is a member of the State of California Federation of Mineralogical Society and the

National Federation of Mineralogical Society.

Meeting held: 1st Wednesday of each month at 7:30 P.M. Potlucks: 6:30 P.M.

Pebble Pups meet each month at 6:00 P.M. prior to the meeting

Place: Performing Arts Center, 800 Hobson Way, Oxnard, CA (Thousand Oaks Room)

Dues: $15.00 per adult; $2.00 per junior member (age 12 to 18 years)

OGMS Officers for 2017 President Stephanie Hagiwara 1st Vice President (Program) Stephanie Hagiwara

2nd Vice President (Show) Diane Cook

3rd Vice President (Field trips) Bob Driskell

Recording Secretary Laura Driskell Treasurer

Miriam Tetreault

Appointed Officers

Corresponding Secretary Laura Driskell e-mail:[email protected]

Displays/Exhibits Open

Editor Karen Kish

e-mail:[email protected] Education Director Donna Knapton

e-mail:info:@oxnard.com

Federation Director John Cook

Historian open Hospitality Janice Albertsen

Librarian Kathy Scharf

Member at Large Adrian Ruiz

Membership Secretary Carolyn Howe Publicity Stephanie Hagiwara

Parliamentarian

Pebble Pups

Laura Driskell

Louisa Carey

Refreshments Scholarships

Candy Marshall Kay Hara

Sergeant at Arms Larry Knapton

Webmaster

Shop Steward Ways and Means

Stephanie Hagiwara

Jean pSmith Larry Knapton

Classes: Silversmithing & Casting: Nancy Bogart, Jean p-Smith, Kirsten Meeker

Lapidary, Opal & Wirewrap: Kay Hara, Brett Johnson

Location: Durley Park, 950 West Hill Street, Oxnard, CA 93030

Editor: All members are encouraged to offer an article of interest or any suggestions as to what their interests

are and what they’d like to see in the Rock Bag. Remember it is your bulletin! Articles can be submitted by

an e-mail attachment or in writing by the 3rd Wednesday of the month. Thanks, Editor

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

President’s Message

At July’s meeting, we dined al fresco during our Summer Potluck. Good food and

companionship made it a successful evening for all. August is Ventura County Fair Time. I

am looking forward to seeing all the fabulous projects our members are displaying, hearing

the bands and visiting the horses. I hope to see everyone there!

Stephanie Hagiwara – President

Program for the August Meeting:

Join us on August 2nd, as we volunteer on the opening day of the Ventura County Fair. It is a pleasure

sharing the excitement of friends and family finding ribbons on the display case of someone they know.

Volunteering involves cleaning glass on the display cases and asking that people enjoy their food & drinks

outside. I consider it an opportunity to look at the display cases without being rushed. Volunteers receive

free entry to the Fair. Can’t make it on Wednesday? It is possible to volunteer on other days at the Fair.

Schedule your volunteer time with Diane Cook.

Stephanie Hagiwara – 1st VP Programs

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

Reminder

We will not be having a Board Meeting on August 9th. We will be having a By-Law Meeting

on August 16th at 7:00 p.m.. We will be discussing potential changes to our most recent

version. All Board members will have a voice and vote on this topic.

Best, Stephanie

August Pebble Pups Program Calling all Pebble Pups! Wednesday August 2th 2017

It is time for the Ventura County Fair! The general membership will be volunteering at the county fair in the Gem & Mineral building for a free day

pass. You are welcome to join up or to come hang with us Pebble Pups at the regular meeting. I have some fun

projects planned so come join us.

New comers always welcome and NEVER go home empty handed!

The meeting will be held in the Thousand Oaks room of the Oxnard Performing Arts Convention Center (800

Hobson Way, Oxnard) the first Wednesday of the month at 6:00pm

Happy Summer, Rocks ROCK!

Louisa

Take a class at Oxnard College

Physical Geology 101 Laboratory, Tuesday Night

"Where the Laboratory and Field Extraordinaire is Formed"

The course is a traditional 3-hour laboratory class that uses lectures, a textbook, and field exercises. Students

explore and study the processes that shape the Earth. The course gives students a hands-on approach to

learning about mineral and rock and mineral identification, interpretation of topographic maps, and aerial

photographs, geologic maps, interpretation of surface land features, earthquakes, and geologic processes.

Field trips will be offered as extra credit to examine local streams and diversion dams, waste water treatment

plants, beach erosion, and hazardous waste sites, and geomorphic processes.

Course Details:

Physical Geology Lab - GEOL RIOIL 002

CRN: 72953

Duration: AUG 14, 2017 -DEC 15, 2017

Days and Time: Tuesday, 7:00pm to 9:50 pm

Transfer Credit: 1 unit to UC and CSU

For more information contact Joseph Saenz at [email protected]

On-line registration at: http://www.oxnardcollege.edu/

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

The Birthstone for August is Peridot

Source: File:Forsterite-

Olivine-tmu14a.jpg -

https://en.wikipedia.org

Source: File:Peridot-USGS.gif -

https://en.wikipedia.org

OGMS Library – Book of the Month for August 2017

Title: Gemstone Adventure Series, The Gemstone Journey, Vol 4 Author: Jewelry Television Publisher: America’s Collectibles Network Inc., 2008 The book of the month for August is a 50-minute DVD that provides a general look at “the journey of a gemstone.” It touches on the formation, mining/collecting, grading, treatments, and faceting of many gemstones, as well as the manufacture of synthetics. It is a well-produced documentary that would be a good primer for people of any age starting an interest in gemstones or for those more experienced looking for an hour of entertainment. Take a few minutes to look over the OGMS Library at the next regular meeting – Kathy Scharf, OGMS Librarian

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

Field Trips and Rock Shows

2017 Field Trip Information (by sponsoring club): (VGMS) Field Trip Leader; Luther Brown. Phone: 805-312-8467 E-mail: [email protected] (OGMS) Oxnard Gem & Mineral Society - www.oxnardgem.com or Facebook Field Trip page: www.facebook.com/OGMS.Excursions/events Use the new sign-up page so we know you plan to come! Pick a trip, get location information, maps, and sign up! http://whoscoming.com/vgms

(VGMS/OGMS/CGMC) Ventura County Fair –

Help will be needed with set-up. Display your rocks, minerals & fossils to public. See Diane Cook,

VGMS.

Tourmaline Mines, San Diego County;

Himalaya Mine; September 23 ($75/person) Ocean View Mine; September 24 ($75/person). Reservations required. Details coming soon; See member Adrian Ruiz for more information. Also search Internet for the mines’ websites for more detailed information.

Trona Gem-O-Rama, Searles Lake, CA

October 15-16. Saturday 7:30AM to 5PM - Sunday 7:30AM to 4PM SLG&MS Lapidary and Show Building

13337 Main St. (corner of Main & Trona Rd.) A fun, if messy, trip. Halite, hanksite, trona and various other salt minerals will be collected. This is a FEE site.

See flyer for more information at:http://www1.iwvisp.com/tronagemclub/FLYER.htm

Via:VGMS ROCKHOUND

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

2017 VENTURA COUNTY FAIR

AUGUST 2 – AUGUST 13, 2017

Fair theme: A Country Fair with Ocean Air GEMS & MINERALS DEPARTMENT Superintendent – Diane Cook

(805) 889-1209 or (805) 648-3376 x 173 [email protected]

Entry Guides are on the fair website: www.venturacountyfair.org Click 2017 Fair, then up on top drop down menu, click on Fair Entry Guides, then scrow down to Gems & Minerals Entry Guide – there you will find all the classes and rules for your entries. Single specimens, cases, jewelry, beading, silver smithing, a Division and

Class for everyone! Share with the public the great treasures we all enjoy. Fair cases and spaces for personal cases are limited. Please call for reservation of space or case between June 3 and June 18, 2017 to Diane Cook at (805) 889-1209 between the hours of 9:00 AM and 7:00 PM. No one is guaranteed a space or case without confirmation from Diane Cook, Superintendent.

The looking-glass world of "contronyms"-

words that are their own antonyms

• Left can mean either remaining or departed. If the gentlemen have withdrawn to the drawing room for after-

dinner cigars. Who's left? (The gentlemen have left and the ladies are left.)

• Dust along with the next two words, is a noun turned into a verb meaning either to add or to remove the thing in

question. Only the context will tell you which it is. When you dust are you applying dust or removing it? It

depends whether you're dusting the crops or the furniture.

• Stone is another verb to use with caution. You can stone some peaches, but please don't stone your neighbor

(even if he says he likes to get stoned).

• Off means 'deactivated' as in "to turn off," but also 'activated,' as in "The alarm went off."

• Weather can mean 'to withstand or come safely through,' as in "The company weathered the recession," or it

can mean 'to be worn away,' "The rock was weathered."

• Out of means "outside" or "inside": "I hardly get out of the house because I work out of my home."

The contronym (also spelled "contranym"): goes by many names, including "auto-antonym," "antagonym,"

"enantiodrome," "self-antonym," "antilogy" and "Janus word".

Via Boulder Buster 9/16; Rockhounder 10/16

ENTRY PICK-UP DAY

10:00 AM – 7:00 PM Exhibits must remain in place for the duration of the Fair. All entries

not claimed on Monday, August 14, 2017 become the property of the

Ventura County Fair and will be discarded.

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

TIPS FROM A JEWELER’S BENCH BRAD SMITH

FIND THE BALANCE POINT

With odd-shaped pendants or earrings it’s often difficult to find the right place to attach a bail or loop so that the piece is balanced and hangs straight. A quick way to make a tool for this is to modify a set of tweezers. Any set of tweezers will work. Spread the tips, sharpen them with a file, and bend the tips at a right angle to point towards each other. To use the tool, suspend the pendant or earring between two sharp points to see how it will hang. -------------

DRILL BREAKAGE

Using a small drill is difficult for a beginner, especially if it is hand held in a flexshaft or Dremel. They are easily broken if you push too hard or if you tilt the drill while it's in the hole. Most problems, however, are the result of buying cheap drills that suffer from poor quality steel or inaccurately ground cutting edges. A good drill from jewelry supply companies is well worth the price. Remember that drilling always goes easier with lubrication. A little wax or oil is all you need. Almost anything will work - Three and One, beeswax, mineral oil, injection wax, car oil, olive oil, or one of the commercial cutting waxes. The lubricant helps to move chips out of the hole and reduces friction of the drill against the side of the hole, keeping the drill cooler.

www.BradSmithJewelry.com =========================================

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

Minutes of the OGMS General Meeting, July 5, 2017

Meeting called to order at 7:35 p.m., Stephanie Hagiwara, presiding.

1st VP: Tonight’s program was the Summer Potluck. Thanks to all the members who brought the wonderful

food for the potluck. We had approximately 40 attendees at the dinner. Adrian Ruiz barbecued tri-tip,

supplied by the club, and it was wonderful. The PACC allowed us to set up tables and chairs in the

courtyard, and eat in the gentle sun and breeze.

The program for August is the Ventura County Fair Field Trip! This has been a fun and educational activity

for the past 4 years. By going to the Fairgrounds and helping out at the Gem & Mineral Pavilion (the Santa

Rosa Hall) for 2 or more hours, you can earn a ticket to enjoy the rest of the Fair! Contact Superintendent

Diane Cook, at 805-340-9026. Diane will leave tickets for you at Will-Call, and you need to check in with her

when you arrive at the Fairgrounds.

September’s program is on Tourmaline (the theme for our November show), by Adrian Ruiz. Adrian is also

leading a 2-day field trip to the Himalayan and Ocean View Mines on September 23rd and 24th.

Hospitality: The hospitality books were out for signing. Pebble Pups were invited to come to the potluck, but

none did. The Ways & Means table was not put out, nor was the library.

Recording: Stephanie asked for a motion to approve the June Meeting Minutes as printed in the Rock Bag.

Brett Johnson so moved, Miriam Tetreault seconded, and motion passed.

2nd VP: Diane Cook will have a show meeting after the VC Fair. Please consider entering your lapidary,

fossils, or jewelry in the Fair!

Membership: Carolyn will have an application to present next week at the Board Meeting.

Federation: John Cook presented the OGMS LuNeal Hailey Scholarship check to CFMS directors.

Refreshments: September meeting volunteers are Janet Bergerson and Carolyn Howe.

Old Business: none

New Business: Stephanie called for a motion to purchase wheels for the Durley classroom. This request

was made of the general members due to the cost involved. Diane Cook made a motion to purchase the

wheels for Durley Park, not to exceed $1200. Motion seconded, all in favor, none opposed, none abstain.

Motion carried.

Announcements: Next General Meeting, at the Fairgrounds, August 2nd. Volunteers needed all day.

No other business was conducted, and the meeting was adjourned at 7:57 p.m., by Stephanie Hagiwara.

Respectfully submitted, July 23, 2017

Laura Driskell, Recording Secretary

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

Agenda for the July 2017 OGMS Board Meeting

Meeting called to order at 7:10 pm, Stephanie Hagiwara, presiding. In attendance: Stephanie Hagiwara, Miriam Tetreault, Kathy Scharf, Carolyn Howe, Jean pSmith, Diane Cook, Adrian Ruiz, and Laura Driskell. Board meeting minutes from June were printed in the Rock Bag. Miriam Tetreault made a motion to approve the Board’s June meeting minutes; the motion was seconded and passed. Officer Reports: 1. Programs, 1st VP Stephanie Hagiwara: August meeting is the VC Fair Field Trip, sign up to volunteer. September, Adrian Ruiz shows tourmaline and discusses where to find it. October, Aaron J. Celestian, Ph.D., of the Natural History Museum of Los Angeles, gives us the latest research that is being conducted at Searles Lake, CA. 2. Show, 2nd VP Diane Cook: Discussion of show poster and mailing cards. Previous board vote was for “Calcite” as the theme, and some comments on changes for the poster. Stephanie asked about skirting, and Diane said she sent the website for ordering the cloth skirting. A meeting will be held in the next month or so, after the County Fair. 3. Treasurer, Miriam Tetreault: Discussion of bills and deposits, since the last month. Diane Cook made a motion to pay the bills; motion was seconded and passed.

Marketing: Stephanie requests more class brochures and marketing materials. Miriam Tetreault made a motion that the cost of the brochures be paid, not to exceed $150. Motion was seconded, and passed. 4. Corresponding Secretary, Laura Driskell: nothing to report. 5. Classes/Shop Steward, Jean pSmith: The Memorandum of Understanding was received, and the insurance certificate will need to be updated. The insurance coverage by McDaniel’s will have an endorsement to cover all attendees. The additional insurance will cost $250 per year from now on; however, this year’s endorsement will be pro-rated. A motion was made by Stephanie Hagiwara to pay the additional endorsement, in the amount of $250 or less. The motion was seconded and passed. 6. Membership, Carolyn Howe: Presented member application from Amy Bruder. Miriam Tetreault made a motion to accept the application for Amy. Motion was seconded and passed. 7. Federation, John Cook: Diane Cook told about the LuNeal contribution to the CFMS Scholarship Fund, which was extremely well received. 8. Library, Kathy Scharf: Kathy converted VHS tapes that were viable to DVD format. Any tapes that were not viable will be thrown away. Any duplicates of DVDs will be donated to the November show for raffle gifts or sold at the book table. Kathy found a Procedural manual from a previous Librarian, and had questions regarding it.

A. The following suggestion was made regarding the fees: Suggestion: An agreement may be made with the Librarian to check out an item for a period of up to 60 days. A fee of $5 may be charged for an item a month overdue, unless it is renewed in person at the next meeting. Renewal may be for 30 days at a time. If the item is not returned within the agreed period of time, the member shall be required to pay the replacement cost for the item.

9. Refreshments: August, Field Trip to VC Fair. September, Carolyn Howe and Janet Bergerson. OLD BUSINESS: A By-Law Committee meeting may be held on the 3rd Wednesday of August, at 7 p.m. NEW BUSINESS: Jean pSmith says she can issue a special code for the membership to get into the new student spaces at the silversmith class. She will send out an invitation to all the members. Announcements: Next Board Meeting date, August 16, 2017 at 7:00 pm. Adjournment: Meeting adjourned by Stephanie Hagiwara at 8:50 pm. Respectfully submitted, Laura Driskell, Secretary, July 23, 2017

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

Road Trip Report: Triassic “Coral Reefs” in Nevada - by Andrew Hoekstra

Source: File:Terebratella sanguinea.jpg - https://en.wikipedia.org

(From the Bulletin of the Southern California Paleontological Society, Jan-Feb, 2016) The great extinction at the end of the Permian resulted in the disappearance of 95% of known species. Life slowly recovered during the Triassic, but there were new forms and communities were different. Modern corals replaced the vanished Paleozoic corals. Brachiopods survived, but in diminished numbers as their old roles in Paleozoic ecosystems were being taken by the rapidly diversifying bivalve mollusks. The Triassic Luning Formation is exposed in the Pilot Mountains and elsewhere in Nevada. At Dunlap Canyon, fossils from a >210 million years old coral community are found beside a good unpaved road (suitable for passenger cars as of Oct. 2012) on BLM land, five miles from Mina and US-95. While not exceptionally well preserved, these Triassic fossils are important and they have been well studied. Mina is about 2.5 hrs from Lone Pine or 1.5 hrs from Bishop. Services are few near Mina; the nearest motels are at Hawthorne, Nevada. Additional fossil sites in this area include ammonites and other fossils from the terminal Triassic and early Jurassic at New York Canyon1, 6, 9 and additional Luning Formation fossils in and around the Berlin-Ichthyosaur State Park 10, 11. Any route taken to Mina will pass locations of geological interest with rocks, minerals, or fossils to collect. To reach the site, turn east onto a well-graded gravel road just north of Mina (likely unsigned but known as Simon Lead Rd. or “dump road”). Drive about two miles, and then keep right at a junction. Continue about 3 more miles into the canyon, keeping left on the main road past another junction. Fossils are found south of the road in the hills with blue-grey limestone ridges. Look for loose fossils like brachiopods on the ground and for small chunks of limestone with corals or sponges. Further into the canyon, before another junction, fossils occur on both sides of the road. Ammonites have been found farther along the road in a different layer of the formation. The main road continues (left fork) and eventually curves back through Cinnabar Canyon to the starting point; driving the entire 21 mile loop is not necessary; just return the way you came at any time. During a short visit, we collected a variety of brachiopods, and also bivalves, gastropods, and star-shaped crinoid (Isocrinus) columns, mostly dark grey or black in color. Colonial corals look like imprints on the surface of the grey limestone. Sponges were my favorite find, their dark cross sections and exteriors contrasting with the limestone matrix in which they are embedded. Sponge, Nevadathalamia cylindrica (Seilacher, 1962) The Luning Formation’s patch reefs were small and transitory in comparison with modern reefs; they formed in calm water and they did not breach the surface. As reefs died, they were buried and replaced by new reefs, leaving multiple reef structures. Within each reef layer a distinct faunal succession has been discerned7. About two dozen varieties of corals3, 7, sponges5 and spongiomorphs form a reef framework. On and around the reefs lived brachiopods4, bivalves, gastropods, cephalopods, echinoids, crinoids, and ichthyosaurs. These reefs occur in the lower member of the Luning formation, where limestone layers and thin shale beds alternate. A middle member of sandstone, conglomerate and shale has few fossils. Ammonites are reported from the basal section of the upper member of the formation, which is composed of limestone and dolomites from sediments deposited in deeper water. Brachiopods: Colonial coral, Areaseris nevadaensis Roniewicz & Stanley, 2013 Upper left – terebratulid, Rhaetina gregaria (Suess, 1854); Center – spiriferid, Balatonospira? cf. B. lipoldi (Bittner, 1890); Upper right – terebratulid, Zeilleria cf. Z. elliprica (Zugmayer, 1880) Lower left – terebratulid, Plectoconcha newbyi

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Oxnard Gem & Mineral Society, Oxnard Ca. August 2017, Volume 55, Issue 8

Sandy & Stanley, 1993; Lower right – spririferid, Spondylospira lewensis (Lees, 1934)

Brachiopods, via: Wickipedia CORALS Corals live attached to a hard surface and most are colonial. Corals were abundant in the later Paleozoic, but those tabulate and rugose corals disappeared in the great extinction at the end of the Permian. Their calcite skeletons preserve well as fossils. Modern scleractinian hexacorals appear in the Middle Triassic and rapidly diversified. Their aragonite skeletons preserve poorly. There is evidence that during the late Triassic corals began to host “zooxanthellae” (microbial algae, such as the dinoflagellate Symbiodinium) inside their bodies8. The symbiotic algae provide extra energy to corals, which helps them to produce the amounts of carbonates necessary to build extensive reef structures. REEFS Inorganic structures or organic buildups are often called reefs without being comparable to modern coral reefs, which have organic frameworks that can resist wave action. A true fossil reef exhibits no bedding as animals were preserved in life position. Organic reefs of the past were often dominated by algae and animals other than coral. Triassic reefs were not yet like modern coral reefs but, during the Mesozoic, corals became the major component of reef frameworks (except when supplanted by rudist bivalves during the Cretaceous). Corals are the dominant reef-forming organisms of the Cenozoic and today. SYMBIOSIS One of the most significant innovations in the history of life is believed to have taken place during the Precambrian, when certain microbes began to live inside of other cells, becoming the mitochondria and organelles found today in all complex eukaryote cells. Other types of symbiosis have repeatedly arisen. Photosynthetic zooxanthellae are found in many corals and also in certain anemones, jellyfish, giant clams, flatworms, sponges, ciliates and foraminifera. Similar algal symbiosis has been suggested for some extinct tabulate corals, fusulinids, sponges, brachiopods, archaeocyathids, and bivalves. Symbiotic chemosynthetic bacteria enable animals (possibly including certain trilobites) to live in inhospitable environments which are food deprived or poisoned by sulfides, such as deep sea hydrothermal vents and sewer outfalls. Offshore of Los Angeles, the outfall of Hyperion Sewer Treatment Plant until recently provided a suitable environment for such symbiosis, and there a gutless clam thrived: Solemya reidi (also, in this clam, sulfide oxidation was first established in animal tissue2; its name has since been revised to Solemya pervernicosa).