3l6 TRANSACTIONS OF THE WAGNER FREE 



form is figured plate i6, figure 2. The same form with a feeble sutural carin 

 is more slender and the undulations of the equator are more marked ; this, 

 which may be called var. intermedia, is figured on plate i6 as figure 3. 



Lastly we have a variety, perincisa (plate 16, figure i), in which the 

 equatorial and sutural carinse are very strong, the wide spirals behind the 

 equator number three or four unusually strong with deep grooves between 

 them, the sutural carina is duplex, all the preceding sculpture is distinctly un- 

 dulated, and the fine spirals have become weak. 



Turritella perattenuata Heilprin. 



Plate 16, figures 5, 9. 



T. perattenuata Heilprin, Trans. Wagn. Inst. i. p. 83, pi. 8, fig. 13, 1887. 

 ? T. tornata Guppy, Quart. Journ. Geol. Soc, vol. xxii. p. 580, pi. 26, figs. 12, 18 ; cf. 

 Gabb, Geol. St. Domingo, p. 240, 1S73. 



Pliocene of the Caloosahatchie beds, Shell Creek and the Myakka River, 

 Willcox and Dall. 



This elegant species belongs to the group which includes, in the Miocene, 

 variabilis, exaltata, cumberlandia, altilira and terebriformis Conrad, tornata 

 Guppy and terstriata Rogers, as will be seen by the remarks under the head 

 of T. terebriformis. The number of accepted names will probably be dimin- 

 ished when sufficient material has been brought together and carefully studied. 



The variations notable in the material which I have brought together, in- 

 cluding several hundred specimens of all ages, may be classified as follows 



1. Variety obsoleta ; surface destitute of spiral sculpture except the angu- 

 lar borders of the equatorial sulcus and a faint line behind the suture. 



2. Variety iindida ; the angular borders of the sulcus elevated into 

 obliquely beaded, rope-like carinae, the hollow of the sulcus without spirals. 



3. Variety perattenuata (typical) ; the hollow of the sulcus with two 

 beaded spirals and one or more on the shoulder behind the posterior carina. 

 Old specimens tend to discontinuity at the suture in the last few whorls. 



This species attains a length of 135.O mm., with a maximum diameter at 

 base of 1 3.5 mm. ; a shell of this size exhibits forty-four whorls. It is very abun- 

 dant on the Caloosahatchie and Shell Creek in the marls. Its nearest living 

 analogue would seem to be T. exoleta L. of the Gulf of Mexico. The origi- 

 nal figure is now supplemented by a better drawing. 



Turritella apicalis Heilprin. 



Plate 16, figures 10, ir, 12, 13. 



Turritella apicalis Heilp., Trans. Wagn. Inst. i. p. 88, pi. 8, figs. 14, 14 a, 1887. 



Turritella cingulata Heilp., op. cit. p. 89, pi. 8, fig. 15 ; not of Hisinger, Sowerby or 



Hupd 

 Turritella mediosulcata Heilp., op. cit. p. 89, pi. 8, fig. 16. 



Pliocene of the Caloosahatchie beds. Shell Creek and Myakka River, 

 Dall and Willcox. 



