NUDIBRANCHS OF THE VANCOUVER REGION 1 65 



The penis is long and cylindrical and armed with minute thorn like 

 hooks. 



The striking characters of this species justified MacFarland in 

 atrributing it to a new genus (of which it is the only member so far re- 

 corded) when he first described it. He subsequently gave a fuller 

 description of it and a figure from which it could be immediately recog- 

 nized. 



Habitat. — So far I have only obtained this species from under the 

 rocks on the beach of Mudge Island. The rocks are only exposed at 

 spring tides, covered with fucus and green algae and lie just above the 

 limits of a Zostera zone. It has been obtained by MacFarland at Monte- 

 rey and by Cockerell at San Pedro, California. 



Genus Triopha (Bergh). 



Triopha Bergh. On the Nudibranchiate Gasteropod Mollusca of the 

 Northern Pacific Ocean (Dall, Explor. of Alaska, I, Art. 6), II, i88o> 

 pp. 261-266 (also in Proc. Acad. Sci . Phila., 1880, p. 112). System 

 der Nudibr. Gasteropoden, 1892, p. 148. Die Opisthobranchien , 

 Bull. Mus. Comp. Zool., XXV, lo, 1894, pp. 184-187. MacFarland, 

 Proc. Biol. Soc, Washington, Vol. XVIII, 1905, p. 48; Bull. Bur. 

 Fish,, Washington, Vol. XXV, 1905, p. 135. Cockerell and Eliot, 

 Jour. Malacol, Vol. XII, 1905, p. 42. 

 Form of body somewhat limaciform; margin of the narrow frontal 



lobe with a series of short simple or composite granulose appendages; 



margin of dorsum with nodulate or short -branched appendages; rhino- 



phores retractile, clavus perfoliate; tentacles short, calciform, the outer 



m.argin in part cleft (auriform) ; branchiae of few tripinnate leaves. 

 Mandibular plates triangular, made up of short, closely set rodlets. 



Radula rather narrow; rhachis with several series (4) of spurious teeth; 



pleurae with several (3-18) rows of larger teeth; lateral teeth many 



(10-18). 



Prostate gland large. Glans penis armed. 



Triopha elioti sp. nov. 



Body. — The body is stout and limaciform and fairly high. The front 

 end rises fairly rapidly and then slopes quite gradually to reach its 

 highest point about half way back just in front of the branchial plumes. 

 Thence it slopes quite rapidly leaving the last quarter of the body low. 

 A well marked veil or frontal margin is present in the form of a semi- 

 circular fold on the edge of which are about 12 small irregularly knobbed 

 papillae. The back is smooth save for the presence of about a dozen 

 small blunt papillae in front of the branchiae and 3 or 4 behind. The 



