210 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



Pupa corticaria, SAY, Nich. Encycl., IV. ed. 3, 1819, PI. IV. Fig. 5. GOTJLD, 

 Bost. Journ. Nat. Hist., III. 397, PI. III. Fig. 19 (1840) ; IV. 358 (1843). - 

 DfiKAY, N. Y. Moll. 50, PI. IV. Fig. 49 (1843). KUSTER, in CHEMNITZ, 

 2d ed., p. 27, Tab. XIII. Figs. 19-20. PFEIFFER, MOD. Hel. Viv., II. 328. 

 -BINNEY, Terr. Moll., II. 339, PI. LXXII. Fig. 4. W. G. BINNEY, Tern 

 Moll., IV. 146 ; L. & Fr.-W. Sh., I. 244 (1869). GOTJLD and BINNEY, Invert. 

 of Mass. [2], 439(1870). 



Carychium corticaria, FERUSSAC, Prodr., No. 3 (no desor.). 



Leucochila corticaria, MORSE, Joum. Portl. Soc., I. 36, Fig. 87 ; PL X. Fig. 88 

 (1864). TRYON, Am. Journ. Conch., III. 307 (1868). ; 



From Maine and Wisconsin to South Carolina and Mississippi. I believe, 

 therefore, that it will prove to be found over all the Eastern Province. 



Animal whitish, darker upon the head and eye-peduncles ; the latter are long 

 and club-shaped ; tentacles short, thick. 



This is a very thin and delicate shell, and has a peculiar transparency, 

 resembling spermaceti. The aperture is somewhat circular, the upper part 



Fig. 113. 



Pupa corticaria. 



being interrupted by the last whorl, and the extremities of the peristome not 

 being connected. The smaller tooth is often wanting, and sometimes both. In 

 the number and position of the teeth it somewhat resembles Carychium exiguum ; 

 but it is less fusiform, and more cylindrical. In general outline, and in the 

 shape of the aperture, it very much resembles P. rupicola, but the parts within 

 the aperture are very different. It is, however, just what the immature shell 

 of that species might be supposed to be, when the dentiform deposits were only 

 commenced, and the peristome thin and unfinished. I am much inclined to 

 believe that it is only a young shell. In the great number of specimens which 

 I possess, the teeth are only rudimentary. 



Jaw slightly arcuate, tapering towards the pointed ends, the centre of the 

 anterior surface marked with longitudinal striae ; concave margin with a slight, 

 broad, median projection. 



