136 



mens I am indebted to Mr. Holland, who has ^ne fresh shell, 

 the color of which he describes as quoted above, and as faintly 

 indicated in the best of the specimens before me. In form it 

 approaches more Pnearly to H. ampliata and H. Jamaicensis 

 than any of the group, which is characterised by an anterior 

 notch or slit in the margin of the aperture. 



I am indebted to Mr. Holland for a variety of Helicina 

 depressa of extraordinary size. Its mean divergence is 140°; 

 greatest breadth .33 ; inch ; least breadth .28 inch ; height .18 

 inch. The corresponding dimensions of an ordinary specimen 

 are 140° ; .24 inch ; .2 inch ; .125 inch. It may be designa- 

 ted by the name of valida. 



A variety of TrocJiateJla Josephintv^ from the western part 

 of the island, presents a type quite distinct from that which 

 served for the description of the species, and which inhabit 

 the eastern part. The spiral ridges are less conspicuous, and 

 are more or less interrupted by various irregularities of the 

 surface. The acute periphery is furnished with very promi- 

 nent vaulted compressed scales, and is of a red color. The 

 inferior surface is of a lemon yellow color, and its spiral striae 

 are rather indistinct. The lower part of the lip is quite thick. 

 This type may be designated by the name of pulchra. Its 

 mean divergence is 100° ; height .29 inch ; greatest breadth 

 .52 inch ; least breadth .44 inch. 



Of Trochatella Tankervillii several types appear quite 

 distinct in extreme specimens, but graduate into each other 

 by innumerable intermediate varieties. In one type, variety 

 «, the spiral ridges are stronger, and the other irregularities 

 of surface are less developed. The last whorl is more convex 

 on both sides of the periphery, which is consequently less acute. 

 This variety approximates most nearly to T. pulchella in form 

 and size. 



