MUSEUM OF COMPARATIVE ZOOLOGY. 147 



color and painting of the shell are unlike any of the described varieties of 

 V. musica. The gr6und is pretty uniformly clouded with a livid purple hrown, 

 with three or four paler bands, which in the young are narrow, distinct, and 

 articulated with rectangular brown spots rather distant from one another ; the 

 surface generally is dotted over with a profusion of brown dots, and there is a 

 tendency toward a band of the dark body color just in front of the ribs, which 

 gives the appearance of a succession of large squarish spots, one in front of each 

 rib. There are eleven ribs on the last and twelve on the preceding whorl ; they 

 are shorter, more pinched up, and much less prominent than in the short- 

 spired varieties of V. musica, which generally have seven or eight very promi- 

 nent ribs, almost like spines. They are in the present species smaller behind 

 and more inconspicuous than in any V. musica I have seen, coronating the 

 suture, and occupying less than half the exposed part of the whorls on the 

 spire. In the adult they are very short, but in the young they are extended 

 nearly to the canal. 



The most important feature, however, and that which leads me to believe 

 that the Texas shell is specifically distinct from V. musica, lies in the nucleus. 

 This is composed of two turns, of which the first is white and inflated, as in 

 most Volutes of the Scaphclla group, and is itself larger than the first two turns 

 of the nucleus of V. musica taken together. The second turn is, if anything, 

 slightly smaller, giving a papillary appearance to the nucleus. The adult shell 

 has four and a half whorls, which with the nucleus form six and a half, against 

 seven and a half of the V. musica of similar length. The youngest specimen 

 of the Texas shell shows seven plaits on the columella, the largest fifteen, of 

 which each alternate one is smaller. I have not been able to find more than 

 twelve plaits on the largest V. musica in the collection. This interesting form, 

 the only true Voluta known from the coast of the United States, should bear 

 the name of Voluta virescens Solander, though Lamarck's later name of V. poly- 

 zonalis is more appropriate. According to various authorities, V. virescens 

 would also have as synonyms V. fulva and chlorosina of Lamarck and V. pusio 

 of Swainson ; the latter a broad variety. The West African habitat assigned 

 to Voluta virescens is probably erroneous, but at all events there can be no 

 question as to its American habitat. 



Genus SCAPHELLA Swainson (em.) 



> Scaphclla Swainson, Zool. 111., 2d ser., II., No. 19, 1832 ; Malacology, pp. 103, 318, 



1840. 

 Caricella sp. Conrad, Journ. Acad. Nat. Sci. Phila., 2d ser., I. p. 120. 



It seems evident that Voluta and Lyria on the one hand and the rest of the 

 Volutes on the other are separated by a greater gap than divides either group 

 above indicated within itself. Some name must be adopted from among those 

 which have been applied to the shells not included in Voluta proper to cover 

 the genus, of which most names in use are indicative of merely sectional di- 



