CERION, GROUP XI. 259 



Aperture brown inside, the outer lip reflexed, often thickened on the 

 face ; parietal callus ridge-like ; parietal lamella small and short. 

 Length 22, diam. 10 mill., but varying from 26 to 19 mill. long. 

 Mr. Maynard collected the types in 1884 on the borders of a deserted 

 plantation about a mile west of Fort Charlotte, N. P. One of these 

 is figured, pi. 42, fig. 37. Nine years later he revisited the spot, 

 finding the plantation cultivated, the bushes uprooted to make place 

 for sisal fields. The shells occurring on the Agave plants in this 

 place were chiefly intermediates between " neglectum " and the 

 alleged subspecies ** S. n. agava." This form agava (pi. 42, fig. 38, 

 one of the type lot, and figs. 39 to 44), which is one of the most 

 abundant in the collections I have seen, is typically larger than 

 "neglectum" dirty brownish- or ashen-white, copiously or sparsely 

 maculate or suffused with purplish- or bluish-brown ; lusterless ; the 

 ribs are nearly regular, usually about 23 (rarely as many as 29) on 

 the penult, whorl. The outer lip is reflexed in a thick flange, and 

 the parietal callus forms a strong raised and straightened ledge. 

 Interior brown, the parietal lamella generally rather short, occasion- 

 ally elongated. It is common throughout the sisal fields west of 

 Nassau. Mr. Maynard traced it about eight miles west and a mile 

 inland. 



A specimen of the agava type in the collection of the Academy 

 was received from Dr. Pfeiffer as glans, and bears his autograph 

 label. 



In the immediate vicinity of Fort Charlotte, near Nassau, the 

 form called S. carlotta Maynard (pi. 42, figs. 45, 46, 47) occurs. 

 " The type locality is at the foot of the hill on which the fort stands, 

 on the north side." The shell is stout in figure, ovate or oblong- 

 cylindric, dull, pale brownish- white with indistinct darker markings. 

 The ribs are rather narrow, lip reflexed and more or less thickened, 

 parietal callus strongly or moderately developed. To the westward 

 of the type locality somewhat larger and heavier shells occur (fig. 

 47), and up the hill, almost under the shadow of the old Spanish 

 fort, a dwarf form (fig. 46) is found, its small stature probably due 

 to the extreme dryness of the place, as Maynard remarks. " S. 

 carlotta " if thrown among a handful of the ordinary "agava" form, 

 could not be distinguished from them, because there are no differ- 

 ences whatever between many specimens. "Carlotta" is merely a 

 name for "agava" from Fort Charlotte. 



