Pidmonifera of 3faine. , 



25 



is banded with twenty to twenty-five thin, sharj), prominent lam- 

 inae, inclined slightly backward and parallel with the lines of 

 accretion; these laminae present a waved appearance on their 

 outer edges, probably produced artificially as they are very elastic. 

 Between these ribs are distinctly seen the incremental lines ; 

 revolving Avith the whorls are also interrupted lines, these are 

 intercostal only. {PI. 2, Fig. 5.) 



Buccal plate, (Fi(j. 52,) slightly arcuate, 

 rounded at sides, irregularly wrinklod longitud- 

 inally ; cutting edge produced in the middle to 

 a rounded beak. 



Lingual meAibrane 77-13-1-13, central plate long, quite narrow, outer posterior 

 angles projecting, having three small denticles. Laterals nearly lozenge shaped, 

 outer posterior angle with two projections; having one large denticle, one 

 smaller outer denticle, and at the inner base of large denticle a minute pro- 

 jection. Uncini broad and short, with one or two minute denticles. {PI. 8, 

 Fkf. 53.) 



The remarks of Dr. Gould, quoted by W. G. Binney, in his 

 "supplement," in connection with this species, were not intended 

 for this shell. Several years ago I sent a description with speci- 

 mens of Punctum minutissimum to the Boston Society of Natural 

 History, iindcr the supposition that it was new, having never seen 

 Lea's description, and Dr. Gould's remarks were in reference to 

 those specimens. 



Helicodiscus lineata, Say. {Fig. 61.) 



Everywhere in company with the smaller species, though no- 

 where abundant. 



Animal nearly white or rather translucent, mottled with small 

 white blotches, body long and narrow, upper 

 posterior portion of foot conspicuously fur- 

 rowed. In motion the shell lies perfectly 

 flat on the extreme posterior portion of 

 body, the superior tentacles standing nearly 

 perpendicularly, and the head Avith inferior 

 tentacles thrust out some way beyond the 

 base of larger tentacles ; eyes scarcely visible 

 fifteen ribs ornament the shell of this species, between which are 



\ 



\Ii 



Fig. 61. 

 From fourteen to 



