MUSEUM OF COMPARATIVE ZOOLOGY. 345 



I may say hero, that in seviiral shallow-water Fissurellaa I Lave observed 

 what 1 believe to be an abortive non-lunctional remnant of tlie verge, in the 

 shape of an elongated pa^jiUa at or near the posterior part of the right tentacle, 

 and having nothing corresponding to it on tlie left side. Having fonnd no 

 Ciinal in tliese organs, I have hesitated to mention them until my discovery of 

 vhat seems to be a functional verge in Cranopsis. 



Family COCCULINIDiE. 

 Genus COCCULINA Dall. 



Cocculina Dall, Proc. U. S. Nat. Mus., 1881, p. 402. Verrill, Trans. Conn. Acad., V. 



p. 633, 1882; VI. p. 202, 1884. Jeffreys, Triton Moll., P. Z. S. 1883, p. 393. 



Fischer, Man. de Conchyl., p. 841, 1885. Watson, Chall. Kep. Gastr., p. 30, 



1885. 

 Tectura sp. Jeffreys, P. Z. S. 1882, p. 672. 



Shell patelliform, not nacreous, symmetrical with an entire non-sinuated 

 margin and a posteriorly inclined apex with a (usually deciduous) spiral nu- 

 cleus; muscular impression horseshoe-shaped, interrupted over the head. 



Animal with a prominent head and muzzle, the males with an intromittent 

 organ at the base of the right tentacle; a single lamellose asymmetrical gill 

 (resembling in form and place of attachment the gill in Acmcea) between the 

 under surface of the mantle and the upper surface of the body from a point 

 above and behind the head, extending around toward the right, and even 

 backward on the right side; attached only at its base. Eyes wanting in the 

 known species. Anus anterior, opening in a papilla above and behind the 

 head. Mantle margin and sides of foot plain, without epipodial papillae or 

 processes, but they are sometimes present behind. Radula with a small or 

 moderate hardly raised rhachidian tooth (the cusp in one species obsolete), 

 three moderate inner laterals with denticulate cusps, a larger denticulate major 

 lateral with a stout and twisted stalk, and on each side a stout base from which 

 spring numerous slender uncini booked at their tips. Formula I 



^ a:(l + 3-3 + l)a; 



There is no jaw. The dentition resembles in a general way that of Parmo- 

 phorus and of some species of Helicina. 



The marked peculiarities of this group, and the discovery in the "Western 

 Atlantic, North European seas, and the Philippines, of species appertaining to 

 it, have secured its prompt recognition from naturalists. Thus, there have 

 been described from the Philippines, — 



Cocculina angulata Watson ; 



from North Europe and the Northeastern Atlantic, — 



Cocculina spinigera Jeffreys, Cocculina pusilla Jeffreys (as Tectura), 



Cocculina corrugata Jeffreys, Cocculina adunca Jeffreys (as Tectura) ; 



