ASTEROIDEA OF NORTH PACIFIC AND ADJACENT WATERS — FISHER 159 



Specimens of Pycnopodia helianthoides examined 



Sta- 

 tion 



2802 

 2863 

 3047 

 3012 

 4222 

 4431 

 4457 



Locality 



Queen Charlotte Sound, British Columbia. 



Puget Sound, Wash 



Southern Washington 



Bellingham, Wash 



Vieinity Port Townsend, Wash 



Oil Santa Rosa Island, Calif 



Oft Point Pinos, Calif 



Duteh Harbor, TJnalaska... 



Vicinity Cape Trinity, Kadiak 



Karluk, Kadiak 



Cordova, Prince William Sound, Alaska. _. 

 Union Hay, Bayne Sound, British Columbia 



Boundary Bay, British Columbia 



Point Simpson, British Columbia 



Nanaimo, British Columbia. 



Barclay Sound, British Columbia 



Straits of Fuca. Port Renfrew, British 

 Columbia. 



Puget Sound, Wash 



San Francisco Bay entrance 



Monterey Bay, Calif _ 



San Diego, Calif.. 



Depth 



238 



67 



50 



11 



39 



38-41 



46-10 



Low tide.. 



Low tide.. 



Low tide.. 



Low tide.. 



Low tide.. 



Low tido.. 



Low tide.. 



Bottom 



Oray sand, pebbles 



Fine sand 



Fine gray sand... 



Green mud 



Oray sand, broken shells. 



Sand, mud, rocks 



Dark green mud.. 



Low tide. 



Low tide. 



Low tido. 



Low tide. 

 Low tide. 

 Low tide. 



Intertidal 

 water. 



and shallow 



Num- 

 ber 



1 



1 



Many. 



Number 

 of rays 



20 



18 



20 



18,20 



15 



21 



20 



18 



18,19 



19 



16, ]uv. 



Juv. 



17, 19 



17 



16 



17 



18 



15, 16 



18,20 



17, 19 



19 



17 



Collection 



U.S.N.M. 



Do. 



Do. 



Do. 

 Albatross, 1904. 



Do. 



Do. 

 Stanford. 

 U.S.N.M. 

 Stanford. 



Do. 

 Albatross, 1906. 

 Stanford. 

 U.S.N.M. 



Do. 



Do. 



Stanford. 



U.S.N.M. 

 Stanford. 

 Do. 



Do. 



Remarks. — This heavy, very active, and voracious sea star is a characteristic 

 member of the intertidal fauna of rocky situations from Yakutat Bay, Alaska, to 

 Monterey Bay, Calif. Its range, however, is much more extreme, the known limits 

 being San Diego on the south and Unalaska Island at the north. South of Monterey 

 region it is not common. Intertidally it frequents rocky situations rich in kelp, where 

 it feeds greedily upon sea urchins, hermit crabs, or any other creature not too large 

 and active to escape. In aquaria it will attack a great variety of animals, including 

 crabs and large holothurians. Its diet undoubtedly includes dead fish and such 

 inactive living ones as it is able to trap with its numerous, almost octopus-like rays. 



When excited by food it moves very rapidly and can execute counter movements 

 more actively than any starfish which I have observed. When under "full sail," 

 with its thousands of tube-feet lashing back and forth, it is an impressive animal, 

 and its numerous cushions of tenacious pedicellariae and the wide expanse of its 

 flexible body make it a formidable engine of destruction. The fact that a large 

 Pycnopodia can bring over 15,000 sucker feet into action against a struggling fish 

 or crab suggests a reason for its success in competition for place and food. 



In an aquarium both Strongijlocentrotus purpuratus and franciseanus (the latter 

 with formidable long spines) were swallowed whole and retained in the body from 

 24 to about 3G hours, when the cleaned test and disarticulated spines were rejected. 

 After a battle with a sea urchin the feot of Pycnopodia are usually liberally beset 

 with the pedicellariae of the urchin, which by their purple color are conspicuous 

 against the pale yellow of the tube-feet. (See pi. 80, ped.) 



