PARMACELLA. 223 



sole light reddish yellow. Shell narrow, convex, of one-and-a- 

 half volutions. Length, 3'5-4-5 inches. 



Spain and Portugal. 



P. MOQUINI, Bourguignat. PL 55, figs. 93-95. 



Uniform brick-red, the rugosities of the mantle slight, mantle 

 unspotted ; back less strongly carinated and tentacles stouter 

 than in the preceding species. The shell is smaller, of a dirty 

 greenish yellow, thinner anteriorly, the nucleus smaller and 

 more oblique. 



Southern France. 



P. GERVAISII, Moquin-Tandon. PI. 55, figs. 96, 9T. 



Olive-brown without spots. Nucleus of the shell greenish 

 yellow, very shining, the blade oval, thick and chalky, only three 

 times as large as the nucleus. 



Southern France. 



According to Moquin-Tandon the nucleus of the shell is 

 always exposed in the living animal. Perhaps it is only a color 

 variety (and not adult) of the preceding species, with which it 

 inhabits. 



Subgenus CRYPTELLA, Webb and Berthelot, 1833. 



The insufficient distinction of this group is in its less distinctly 

 spiral shell. They are inhabitants of the Canary Islands where, 

 during eight or nine months in the year their activity is sus- 

 pended, and they remain concealed under the large blocks of 

 lava with which these islands are covered. During the rainy 

 season, and especially at night, they quit their retreats and 

 commit great havoc in the gardens. The peasants destroy them 

 by thousands, yet their numbers do not appear to diminish. 



P. CALYCULATA, Sowb. PI. 55, figs. 98-3. 



Animal elongated, narrow in front, trisulcate, the middle sulcus 

 larger, tail trigonal, carinate, acute ; shield tongue-shaped ; oliva- 

 ceous, with brown spots and streaks, the neck and head bluish, 

 the foot deeper blue. Shell retaining a vestige of the embryonal 

 peristome visible below. Length, 2'5-3'5 inches. 



Canary Islands. 



The spire of the embryonic shell is not apparent. Figs. 99-1, 

 represent the embryo shell and temporary operculum (see p. 



