FISSURELLID^. 329 



Parmophorus, Blainv. 



Etym. — Farme, a shield, and phor-eus, a bearer, Duck's-bill 

 limpet. Si/n. — Sentus, Montf. 



Distr. — 12 sp. East Indies, Philippines, Australia. Fossil, 3 

 sp. Eocene; Paris basin. P. aus^raZis, Bl. (Ixxxiii, 21 ). 



Shell lengthened-oblong, depressed ; apex posterior ; front 

 margin incurved. Muscular impression horseshoe-shaped, elon- 

 gated. The shell is smooth and white, and permanently covered 

 b}^ the reflected borders of the mantle. The animal is black, 

 and ver}^ large compared with the shell ; its sides are fringed 

 with short cirri, and its eyes sessile on the outer bases of thick 

 tentacles. Occurs in shallow water, walking freelj^ 



TUGALiA, Gray. Shell cancellated, with crenulated margin. 

 P. elegans, Gray. 



COCCULINA, Dall. 



Distr. — 2 sp. New England, deep waters. G. Eathhuni, Dall. 



Shell patelliform, apex posteriorly inclined, with a deciduous 

 spiral nucleus ; margin entire. 



Animal blind, with prominent head and muzzle; two tentacles; 

 gill single, plumose, asymmetrical, extending between the under 

 surface of the mantle and the foot (from a point above and 

 behind the head) backward on the right side ; anal opening above 

 and behind the head ; mantle-margin plain ; margin of the foot 

 without processes, excepting a single filament on each side. 

 Radula with a small or moderate rachidian tooth, three incon- 

 spicuous and a fourth larger, dentate laterals, uncini numerous. 

 The male has a verge permanently exserted from the inner side 

 of the right tentacle. 



The shell resembles that of the Patellidae, but the animal is 

 more nearly allied to the Fissurellidse. Mr. Dall has formed a 

 family for the two species known. 



Addisonia, Dall. 



Etym. — In honor of Prof. Addison E. Verrill, of Yale College. 



Distr. — 2sp. New England, Mediterranean Sea. A.paradoxa^ 

 Dall. 



Shell ovate, subconical, strongly asymmetrical with curved 

 apex ; no epidermis ; margin plain. 



Animal with two tentacles ;'no eyes ; foot and mantle without 

 tubercles or processes ; gill composed of leaflets as in Patella, 

 the series starting on the right behind the head and continued 

 within the mantle-edge backward, the body of the animal being 

 asymmetrically placed with regard to the aperture of the shell 

 to afford room for the enormous series of branchial leaflets ; anus 

 opening behind and above the head slightly to the right of the 

 median line, and indicated by a small papilla. Radula with 

 22 



