77 



nates very obtusely ; mostly covered by tlie expansion and thickening 

 of the lip. 



Greatest breadth 2.98 inches; least breadth 2.45 inches; height 

 1-2 inches. 



This largest of all the terrestrial shells of Jamaica is as remarkable 

 for the character of its umbilicus, as for its magnitude. This species 

 is intermediate between H. patina, II. acuta, and H. fluctuata. 



Helix valida. Shell hemispherical above, moderately convex 

 beneath, with a very slight sharp carina on the periphery, which is 

 otherwise well rounded : above dark reddish brown, often blackish 

 along the suture, paler at the apex, often paler beneath ; with a nar- 

 row pale band at the periphery ; lip brown : surface rather finely but 

 strongly and densely granulated, except near the apex : spire very 

 convex and much elevated : whorls five and one-half, quite convex, 

 with a rather deep suture : aperture much expanded above and later- 

 ally, transversely auriform ; with the lip well reflected and thickened ; 

 Vv-ith four teeth, which are similar to those of H. Bronnii : umbilicus 

 wanting. This shell resembles H sinuata in its sculpture and in the 

 v.hite line and delicate keel along the periphery : in respect of the 

 teeth it resembles II. Bronnii. Last summer a specimen was loaned 

 to me by Mr. Cuming as H. Bronnii. This species differs from both 

 of the above in the much dilated aperture. 



Greatest breadth 1.4 inch ; least breadth 1.1 inch ; height .8 inch : 

 of a small variety, greatest breadth 117 inch ; lea.st breadth .07 inch ; 

 height .73 inch. 



Helix fortis. Shell depressed, suborbicular, subconic, moder- 

 ately convex beneath, with a slight sharp keel along the periphery : 

 (reddish brown }) : surface rather strongly granulated except on the 

 upper whorls : spire between convex and conic, but little elevated : 

 whorls nearly five and one-half, convex next below the suture, and 

 next above it very concave, forming a shallow spiral furrow ; with 

 the suture lightly impressed : aperture with the same form and char- 

 acter of lip as in H. sinuata ; with three robust teeth on the lower 

 side, of which the two on the right have, externally, corr,esponding 

 furrows, which are long and deep : umbilicus wanting. 



Greatest breadth 1.44 inch; least breadth 1.19 inch; height .75 

 inch. 



^= Many groups in all the principal genera of land shells in 

 Jamaica present phenomena precisely similar to the following exam- 

 ple, which is pow brielly stated, as an apology for both occasional ex- 

 5 



