CERION, GROUP II. 185 



whorl usually rather compressed and tapering below, ascending in 

 front. Sculpture of moderately strong ribs, which are nearly regular 

 on the cone, but widely and more or less irregularly spaced on the last 

 three whorls, about 16-20 in number on the penult, whorl. Aperture 

 ovate, purplish-brown in the throat; peristome flesh-tinted, reflexed, 

 usually very much thickened beyond the reflection ; parietal margin 

 heavily calloused, often forming a narrow ridge. Parietal lamella 

 strong and about a third of a whorl long. Axial lamella strong, 

 ascending about one whorl. 



Length 27, diam. 12J, length of aperture 12 mill. 



Length 28, diam. 13, length of aperture 11^ mill. 



Length 31, diam. 13, length of aperture 12J mill. 



Little Cayman Island, on the west end. 



Strophia pannosa MATN., Contrib. to Sci. i, p. 10, pi. 1, f. 5, 6, 



13 (anat.), pi. 2, f. 1, b, c C. pannosum PILS. & VAN., P. A. 



N. S. 1896, p. 319. Strophia fusca MAYN., t. c., p. 77, fig. 12, re- 

 peated on pi. 7, f. 19, 19a (July, 1889). Strophia intermedia 

 MAIN., t. c., p. 13, pi. 2, f. 3, 3b (April, 1889) Strophia copia 

 MAYN., t. c., p. 22, pi. 1, f. 1, 3, 7-12 (anatomy) ; pi. 2, f. 8, 8b 

 (shell) Strophia perplexa MAYN., t. c., p. 71, fig. 7, pi. 7, f. 15, 

 I5a. Strophia glaber MAYN., t. c., p. 25, pi. 2, f. 10, Wb Strophia 

 parva MAYN., t. c., p. 24, pi. 2, f. 9, 9&. S. lineota MAYN., t. c., p. 

 20, pi. 2, f. 7, 7b. 



This is the largest Cerion of the Cayman Islands. The types 

 measure 31.8x14.2, and 30.8x12.5 mill. The typical form may be 

 known by the irregular, rather wide-spaced riblets. It varies from 

 a subcylindric to an almost oval form. Mr. Maynard writes: " The 

 Ragged Strophia occurs on the west end of the island of Little Cay- 

 man, living on the coarse vegetation which grows among the rocks 

 that lie just above the beach. I have never found them east of the 

 little cove, on the north side, called Bloody Bay, where the rocks of 

 what is known as the Iron Shore terminate, nor east of the few 

 houses which constitute the only settlement on the key on the south 

 side ; thus they occupy a line, somewhat broken, of a few yards in 

 width and about three miles long. This narrow strip was occupied 

 by them almost exclusively, insomuch so that out of three hundred 

 Strophias that I gathered in a two-mile walk, twelve only were of 

 another species (S. levigata}. 



" In habit they differ from many of the species occurring on the 



