TETHYS-ANTILLEAN. 77 



Shell of the usual form, very thin, and provided at the beak with 



a strong raised plate above, which is not found in European species. 



Near Santa Cruz, Teneriffe, Canaries (Orb.). 



Var. ^EQUOREA Heilprin. PI. 35, figs. 33, 34, 35. 



" Length about 4? inches. Body broadly oval, with a moderately 

 elongated neck ; tentacles cylindrical, slit at the extremity ; buccal 

 lobes broad, infolded ; opereular cavity on a slightly raised papilla " 

 Swimming lobes very ample, free, united behind only at their insertion 

 jar back on the foot, which seems short posteriorly. Right edge of 

 mantle deeply sin used at its posterior third, with a short excurrent 

 siphon. Genital orifice slightly in front of, and below the anterior 

 insertion of gill. Opal-gland with a single orifice about 6 mill, 

 back of genital orifice. 



Color (in alcohol) light olive-gray, with very sparsely scattered 

 irregular and unequal rings, traced in narrow black lines, and rang- 

 ing from 3 to 5 mill. diam. There are also a few irregular black 

 lines. Insides of swimming lobes and the mantle unicolored brownish- 

 drab, free from markings, except for a couple of small black blotches 

 within left lobe. 



Shell with a moderately strong layer of lime at the apex, thick- 

 ened, calloused, and reflexed backward in an erect plate (somewhat 

 like a Pholas valve) ; outer layer yellow, membranous ; posterior 

 sinus rather deeply concave, nearly half the shell's length, and form- 

 ing an angle with the outer lip. Length about 42 mill. 



Bermuda, in shallow water, south side of Castle Harbor, opposite 

 Tucker's Town. 



The above description is from the type collected by Professor 

 Heilprin. It is considerably contracted and the shell has been re- 

 moved. The original description was also from the alcoholic (not 

 the living) animal, the length being supplied from memory. As 

 Heilprin remarks, this form differs from dactylomela and ocellata in 

 lacking the markings on the mantle and the insides of swimming 

 lobes ; moreover in this individual the black circles are very few in 

 number and delicately outlined, and the swimming lobes are not 

 violet bordered. As it was not described living, no complete com- 

 parison can be made with d'Orbigny's circumstantial account of 

 ocellata. The identity of the Bermuda Aplysia commented upon by 

 Dobson, that collected in the Bahamas by Dr. Dolley, and the A. 

 schrammii of Deshayes, with the present form remains problematic 



