INSTITUTE OF SCIENCE, PHILADELPHIA. 29I 



primaries and an equal number of intercalary simple threads; outer lip thick- 

 ened, not reflected, slightly sulcate in harmony with the external spirals; 

 body with a well-marked subsutural ridge and notch outside of it, and with a 

 moderate callus ; pillar short, with a tliick, elevated callus and a strong plait 

 about the middle; canal short, reflected; varix swollen, not very prominent; 

 suture appressed, distinct. Lon. of shell 22 ; max. diam. 7.5 mm. 



This is a well-marked little species with much such a sculpture as Lam- 

 panclla transecta Dall, but immediately recognizable by the plait on the pillar. 



Clava caloosaensis n. s. 

 Plate 14, figure 3 a. 



Pliocene of the Caloosahatchie and Shell Creek, Dall and Willcox. 



Shell acute, nucleus wanting, remainder exhibiting two smooth minute 

 and fifteen gradually enlarging sculptured whorls; the earlier whorls show 

 four small revolving spirals with the anterior pair larger and no transverse 

 ribs ; the peripheral thread soon shows nodulations, and several fine threads 

 appear on each side of it; later the sculpture resolves itself into three flattened 

 spirals with equal channelled interspaces minutely undulated, at first with 

 regularity, afterward with more or less irregularity, the points of the waves 

 nodulous and the spirals keeled on their posterior edges and bevelled ante- 

 riorly; gradually the antesutural band becomes more prominent, wider and 

 more strongly nodulous than the others, which are alternated in size and 

 amount to four beside that on which the suture is wound; on the last whorl, 

 in front of the sutural nodulous band, there are ten elevated spirals, becoming 

 less alternate in size and feebler anteriorly ; the canal and the base about it 

 are free from spiral sculpture or show it very faintly ; the transverse sculpture 

 is not regular enough to be termed ribs anywhere on the shell, and is chiefly 

 limited to the nodular undulations of the spirals and a swollen varix at the 

 end of the first third of the last whorl ; the surface when perfect is brightly 

 polished ; the suture is distinguished by its nodulous band ; the spire increases 

 regularly ; the outer lip is thickened, swollen, and shows a deep sinus at the 

 junction with the body, where there is no distinct subsutural lamina; it is 

 feebly grooved inside; the body is callous and a broad callus is reflected over 

 the pillar; the canal is small, narrow and sharply recurved. Lon. of shell 27 ; 

 max. diam. 8.5 mm. 



This species resembles C. cliipolana, but may be distinguished by the dif- 

 ferent sculpture and less attenuation of the early whorls, the absence of dis- 

 tinct ribbing and generally less prominent sculpture, and the presence of a 

 predominant spiral band in front of the suture. 



There is an indeterminate species of Clava in the Miocene of Bowden, 

 Jamaica, but the genus has been supposed to be absent from the Antilles. 

 There is, however, in the collection of the'National Museum a broken speci- 

 men of a recent species of Clava, resembling C. Kochii Phil., which was collected 



