THE UTILIZATION OF ECHINODERMS AND OF 

 GASTEROPOD MOLLUSKS 



H. P. KJERSKOG-AGKERSBORG, B.S., M.S. 

 Department of Anatomy, Long Island College Hospital, 

 Brooklyn, New York 



The Puget Sound region, in the State of Washington, 

 is noted for the wonderful abundance and diversity of its 

 fauna. The region is also noted for its several groups of 

 archipelagoes, of which the San Juan Archipelago is an 

 especially beautiful one. 



Around the shores of these islands, echinoderms are 

 found in great profusion. Particularly noticeable are 

 the common forms of starfish, sea urchins, and sea cu- 

 cumbers. The most common starfish are Piaster ochra- 

 ceus and Evasterias troschelli, which show, respectively, 

 considerable substantive and merestic variation. In the 

 environs of Bremerton, the latter finds more congenial 

 conditions than any of the other common species, and 

 there it occurs in a ratio of 25 to 4 of the former, while in 

 the San Juan island group, P. ochraceus is by far the most 

 numerous. Besides these two species, P. paucispinus and 

 many others are also found, but in smaller numbers. The 

 twenty-rayed starfish, Pycnopodia helianthoides, occurs 

 quite plentifully at various places, e.g., Bremerton, Grif- 

 fin Bay, East Sound, etc. Sea urchins, Strongylocentro- 

 tus drobachiensis, S. purpuratus, 8. franciscanus are very 

 numerous, especially the former. At low-water, 8. dro- 

 bachiensis may be seen in the bays of the northern part 

 of the sound in large patches, and at a depth of only four 

 meters. 8. f ranciscanus, which becomes very large — 7 to 

 13 centimeters in diameter — is found just below low- water 

 mark ; I have seen it in large numbers in the vicinity of 

 the Biological Station at Friday Harbor. The most 

 noticeable species of sea cucumbers are Cucumaria japon- 

 ica (Semper), C. chrondjelmi (Theil), and Siichopus call- 

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