Jamaica land shells, I have been indebted to the liberality of Mr. 

 Cuming. 



Geomelania Jamaicensis, Pfr. Shell conic-cylindrical ; whi- 

 tish ; densely sculptured with strong transverse* somewhat angular 

 ribs, which become obsolete only on the anterior extremity of the last 

 whorl ; spire with rectilinear outlines ; apex truncate w^ith the loss of 



whorls; nearly seven whorls remaining, rather convex, with a 



well impressed suture ; aperture ovate, widely and deeply effuse ; la- 

 brum much thickened, retlected, very much produced in the lower 

 part ; labium rather thick, separated by a slight groove from the 

 penultimate whorl, separated above from the labrum by a small 

 sinus. 



Mean divergence 16°; length .66 inch; greatest breadth .2 inch ; 

 least bi'eadth .16 inch. 



Geomelania minor. This may be only a variety of the preced- 

 ing, but the dimensions given below are those of the largest, among 

 several hundreds, which we have seen. The most essential difference 

 is in the aperture, which is but slightly effuse ; the labrum is through- 

 out much expanded convexly, and is by no means so disproportion- 

 ately produced in the lower part. The apex is truncate with the loss 

 of 6 or 7 whorls. 



Mean divergence 14'^ to 15"; length .41 inch ; greatest breadth .13 

 inch; least breadth .14 inch. 



Geomelania expansa. Shell much elongate, conic ; whitish ; 

 rather densely sculptured with strong transverse somewhat arcuate 

 ribs, which are flattened on the forward side, are less regular than in 

 G. minor, and are obsolete on the anterior half of the last whorl ; 



spire with rectilinear outlines ; apex truncate with the loss of 



whorls ; nearly seven whorls remaining, moderately convex, with a 

 well impressed suture ; aperture avate, much expanded laterally, 

 widely and rather deeply effuse anteriorly ; labrum but little thicken- 

 ed, slightly reflected above, more reflected and widely spread below ; 

 labium rather thin, a little reflected into the concavity of the central re- 

 gion of the penult whorl, to which it is appressed. 



Mean divergence 18°; length .53 inch; greatest breadth .185 

 inch ; least breadth .15 inch. 



Geomelania elegans. Shell cylindrical; whitish; elegantly 



* In these papers the word transverse is used in reference to the direction of 

 growth, in distinction from spiral, and of course without any reference to the axis 

 'the shell. 



