The West American Scientist. 155 



V — GYMNOSPERM^E. 



i. Juniperus communis L., abundant at 8,200 feet and up- 

 wards. The berries form part of the food of robins (merula 

 migratoria). 



2. Picea engelmanni (Parry) Eng. , Short creek and Willow 

 creek. 



3. Picea pungens, Eng., Short Creek and Willow Creek. 



4. Pinus ponderosa var. scopulorum, En^., abundant, Short 

 Creek, Willow Creek, etc. T. D. A. Cockerell. 



West Cliff, October 7, 1889. 



PRELIMINARY NOTES ON THE GEOLOGY OF 



THE ANA CAP AS. 



(Read before the Santa Barbara Society of Natural History, August, 1889.) 



The group of islands known as the Anacapas are more exclu- 

 sively of volcanic origin than any other of the Channel 

 Islands, the base from the exposure above the level of the ocean 

 being composed of black vesicular basalt, capped in many places 

 by a trachytic rock of a more recent lava flow, and at some 

 points on the most elevated portions of the islands covered by a 

 drift formation, among which are found jasper, chalcedony, and 

 other fragmentary metamorphic rocks. 



Where these metamorphic rocks are found there is abundant 

 evidence that the aborigines, who inhabited the islands, fre- 

 quented the place of deposit for the purpose of selecting rocks 

 suitable for the manufacture of their arrow and spear points. 



An unimportant deposit of limestone exists on the middle 

 island, and a vein of chalcedonic quartz was found near the east- 

 ern end of the larger island; this was also used for the manu- 

 facture of weapons and knives. 



Amygdaloides of chalcedony are very abundant, filling the 

 almond-shaped cavities in the basalt. 



An article on the geology of the Channel Islands, including the 

 Anacapas, with geological sections, the result of the studies of the 

 islands during the past twelve years, is being prepared, and will 

 be presented to this society at its next meeting. 



There are many things connected with the fauna and flora of 

 these islands which are of much interest to students of natural 

 history, and the scenery equals in variety and grandeur many of 

 the most noted localities of other countries, a fact which our 

 local artists are making known. 



The land shells of the islands are peculiar; the only helicoid 

 land shell found on the Anacapas, Helix Avresiana, heretofore 

 noted from San Miguel, Santa Rosa and Santa Cruz, is found 

 but sparingly on the Anacapas, but the writer brought a few liv- 

 ing specimens and planted a colony in the foothills of the Santa 

 Ynez Range, back of El Montecito, where it is hoped they may 



