1913.] Clark, Echinoderms from .Lower California. 217 



Station 5694. Southwest of Santa Cruz Island, California, 640 fms. 



Station 5695. Southwest of Santa Rosa Island, California, 534 fms. 

 Bottom Temp., 38.9°. 



Station 5698. Off Monterey County, California, 475 fms. Bottom 

 Temp., 39.9°. 



Station 5699. Southwest from Monterey Bay, California, 659 fms. 

 Bottom Temp., 37.9°. 



Bathymetrical range, 475-659 fms. Temperature range, 39.9°-37.9°. 



One hundred and fifty-three specimens. 



Ophiacantha rhachophora. 



H. L. Clark, 1911. Bull. U. S. N. M., No. 75, p. 201. 



There is always room for doubt in the identification of small Ophia- 

 canthas and the occurrence of this species on the coast of California and 

 near Cape St. Lucas is certainly unexpected, but after comparing the present 

 specimens with others from Bering Sea and Japan, I think they may fairly 

 be called rhachophora. It is quite likely however, that the young of several 

 species are now included under that name. The largest of these specimens 

 has the disk only 7 mm. across. 



Station 5683. Off Cape St. Lucas, Lower California, 630 fms. Bottom 

 Temp., 39.1°. 



Station 5693. Northwest of San Nicolas Island, California, 451 fms. 



Station 5695. Southwest of Santa Rosa Island, California, 534 fms. 

 Bottom Temp., 38.9°. 



Twelve specimens. 



Ophiocoma sethiops. 

 Lutken, 1859. Add. ad Hist., pt. 2, p. 145. 



Only a single specimen of this common Panamic species is in the collec- 

 tion. It is a large adult from Angel de la Guardia Island, Gulf of California. 



Ophiocoma alexandri. 



Lyman, 1860. Proc. Boston Soc. Nat. Hist., Vol. 7, p. 256. 



There is a good series of this less common species but it was only found 

 at one locality. 



San Francisquito Bay, east coast of Lower California. Ten specimens. 



