FAUNA OF THE ALEUTIAN ISLANDS AND ALASKA PENINSULA 373 





Figure 3. — The only large 5-rayed starfish of the Aleutian Islands, Asterias 

 amurensis. This species is about 1 foot in diameter. Unalaska, August 18, 

 1937. 



frequently (on six islands). These are slender, six-rayed star- 

 fishes, noted as dark green, gray, tan, or purplish red. 



No other Pacific Coast form resembles the 20-rayed starfish, 

 Pycnopodia helianthoidcs (fig. 4). Specimens were taken at King 

 Cove, 35 miles east of Unimak Island, but not in the Aleutian 

 Islands proper. No doubt it occurs at the east end, at least, of the 

 chain. 



SEA URCHINS 



Strongylocentrotus drobachienms, the green sea urchin, is one 

 of the most common inshore animals of the Aleutian Islands 

 (fig. 5). In many places it is possible to look down from a boat 

 through the clear water and see thousands of individuals side by 

 side in a submarine garden of green. It occurs on rocky bottoms 

 more frequently than on sand. Several specimens dredged from 

 deep water (30 fathoms) off Sanak Island were a faded brown in 

 color. Sea urchin spines are so predominant in the refuse heaps 



