MACROCERAMUS. 385 



liquely towards the margin of the lingual membrane, very short and bearing 

 two stout, blunt, short cusps, the inner the larger, also thrown obliquely to- 

 wards the outer margin of the membrane ; both of the cusps bear distinct cut- 

 ting points, the outer one small, the inner one narrow, blunt, almost as long as 

 the base of attachment. There are no distinct marginals, the laterals decreas- 

 ing in size as they pass off laterally, those at the edge of the membrane hav- 

 ing one large inner cutting point, and several outer irregular smaller ones. I 

 have given a group of centrals and laterals, a group of laterals, and an extreme 

 lateral or marginal. 1 



I have had no opportunity of examining M. Kieneri. 



Macroceramus Kieneri, PFEIFFER. 

 Vol. III. PI. LXIX. Fig. l. 



Shell fusiform, attenuated-cylindrical, whitish, or grayish clouded and mar- 

 bled with brown; spire acuminate; whorls from 9 to 13, rounded, with numer- 

 ous oblique, prominent stria; or ribs ; suture impressed, crenulated by the ex- 

 tension of the alternate ribs across it ; aperture rounded, oblique ; peristome 

 thin, somewhat reflected ; axis impressed, not truly perforate ; on the last 

 whorl a colored line revolves ; this is sometimes raised a little from the sur- 

 face, and sometimes is sharp like a delicate carina. Length, 18 mill. ; diameter 

 of antepenultimate whorl, 6 mill. ; of aperture, length 4^, breadth 4^ mill. 



Pupa unicarinata, BINNEY, Terr. Moll., I. Not LAMARCK. 



Bulimus Kieneri, PFEIFFER, Proc. Zobl. Soc., 1846, 40 ; Mon. Hel. Viv., II. 79 ; 



in CHEMNITZ, ed. 2, 131, PL XLII. Figs. 23, 24. REEVE, Con. Icon., 463. 

 Cylindrella pontifica, GOULD, Proc. Bost. Soc. Nat. Hist., III. 40 (1848) ; Terr. 



Moll., II. 306, PL LXIX. Fig. 1. CHENTJ, Man. de Conch., I. 446, Figs. 3305, 



3306 (1859). 



Macroceramus pontificus, "W. G. BINNEY, Terr. Moll., IV. 137. 

 Macroceramus Kieneri, PFEIFFER, Mon. Hel. Viv., IV. 689, not of Vol. VI. - 



TRYON, Am. Journ. Conch., III. 301 (1868). W. G. BINNEY, L. & F.-W. 



Sh., I. 221 (1869). 



In the Florida Subregion, both on the mainland from the Miami Country to 

 Tampa Bay and on the islands from Key West to Key Biscayne. The true 

 M. Kieneri has also been found in Mexico, in Cuba and Jamaica. 



Animal whitish, translucent, a little darker above the head ; body very short, 

 terminating in a blunt extremity, eye-peduncles of moderate length, of nearly 

 equal diameter throughout, terminating in a rounded bulb; tentacles very short, 

 nearly rudimentary ; ocular points large and black. 



When in motion, the axis of the shell is parallel with the line of progress, 

 and lies almost horizontally. The rapidity with which the animal moves is 



l Similar dentition is found in M. turricula, Pfr., of Cuba. See Proc. Acad. Nat. ScL 

 Philad., 1875, PI. XX. Fig. 9. 

 VOL. iv. 25 



