MARINE BIOLOGY ON THE PACIFIC COAST 

 its position on the rocks is the occasion for its 

 extensive use as food. The body is dried entire 

 and shipped to the Orient by the ton, and canned 

 as a table delicacy. The snell of the abalone is 

 noted for its brilliancy of coloring, more varied 

 and more highly colored than the mother-of-pearl, 

 running through a marvelous range of tones of 

 green, blue, red, purple, and violet. Its thickness 

 and colors make possible its utilization in industry, 

 for curios and je\yelry, and for many of the various 

 articles into which mother-of-pearl is manufac- 

 tured. The abalones also produce fine, baroque 

 and blister pearls of exceptional beauty in form 

 and color. The blister pearls are. usually formed 

 over the internal scar caused by the penetration 

 of a small burrowing lamellibranch (Pholadidea 

 parva or sigitata or rarely Martesia intercallata and 

 Adula stijlina, PI. XVIII, figs. 4-7), through the lining 

 nacre. Six species are known on this coast. The 

 green abalone (Haliotis fulgens, PI. XVIII, fig. 3) 

 has been extensively used for drying and canning. 

 Overfishing and the red water of 1904 have locally 

 all but exterminated it. The black abalone (ti. 

 cracherodii, PL XVIII, fig. 1) because of its uniform 

 color and hardness is extensively used in the button 

 industry. The red abalone (H. rufescens, PL XVIII, 

 fig. 2) because of its hardness and brilliant colors 

 is much employed in the manufacture of curios 

 and jewelry. 



Marine mammals. The marine mammals of the 

 Coast have been greatly reduced in numbers by 

 the whale fisheries formerly centered at Monterey 

 and by the fur trade. The sea otter (Latax lutris). 

 great bands of which formerly basked in the kelp, 

 is all but extinct. The pelagic sealing of the north 

 is depleting the fur-seal (Callotqria alascana) herd 

 found off northern California in the winter, and 

 only a remnant of the once abundant northern 

 elephant seal (Macrorhinus angustirostris) now 

 persists at Guadalupe Island. Travelers by steamer 

 may still see the California gray (Rhachianectes 

 glaucus) and the Pacific sulphur-bottom whales 

 spouting in the Santa Barbara Channel or a squad- 

 ron of whale killers (Orcinus rectipinna) cruising 

 along the coast. Porpoises (Phocaena phocaena) 

 and harbor seals (Phoca richardi) still enter San 

 Diego and San Francisco bays occasionally. Sea- 

 lions (Eumetopias stelleri) of the Seal Rocks off 

 the Cliff House at San Francisco and of more south- 

 ern waters (Zalophus calif ornianus) are gradually 

 disappearing as the result of destruction by fisher- 

 men whose nets and catch they destroy. 



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