INSTITUTE OF SCIENCE, PHILADELPHIA. 43 



Cancellaria reticulata LinmS. 

 Cancellaria reticulata Linn^, Lam. An. sans Vert. vii. p. 112, 1822. 



This well-known shell was found in the Post-Pliocene of South Carolina 

 (Post-Pleioc. Foss., pi. x. fig. 6) by Holmes, and in North Carolina by Emmons 

 (Geol. Rep., p. 255, fig. 119, 1858), who gives no locality, but enumerates it 

 among his Miocene fossils, where it certainly does not seem at home. A Mio- 

 cene analogue exists in the C. Icevescens Guppy from Jamaica (Quart. Journ. 

 Geol. Soc. xxii. pi. xvii. fig. 12, 1866) and the preceding species has also an 

 analogue in the Jamaica Miocene [opus cit., pi. xvii. fig. 11), which apparently 

 differs from C. Conradiana chiefly in the situation and form of the columellar 

 plaits. This is the Cancellaria Barretti Guppy. 



The West Indian recent C. nigosa Lam., C. similis Sow., and similar species 

 have a precursor in the C. Moorei Guppy (opus cit., pi. xvii. fig. 7), but nothing 

 of this sort appears among our Floridian fossils, so far. The early Cancellarias 

 of the United States appear to belong rather to the Trigonostoina group. 



Thus we have the Trigonostoina carolinensis Emmons, from the Cape Fear 

 and West Florida Miocene, represented in the recent fauna by T. tenera Phil., 

 which also appears in the Caloosahatchie beds. There is another species, C. 

 pcrspectiva Conrad, from the Miocene of Duplin County, North Carolina, which 

 belongs to the same group, but is differently ornamented. 



Of the small Trigonostomas there are a dozen species referred to the 

 Eocene, of which several will perhaps fall into synonymy at a later date. 

 Several are closely related to certain species of the recent fauna, such as T. Smithii 

 Dall and T. Agassizii Dall. When full and continuous series have been ob- 

 tained from our various Tertiary beds, the genealogy of many of the recent 

 species of our fauna will be readable almost at a glance. The intimations, 

 which even our present imperfect knowledge affords, are extremely interesting. 



Cancellaria venusta T. & H. 

 Plate 3, figure 12. 

 Cancellaria venusta Tuomey & Holmes, Pleiocene Foss of S. Carolina, p. 144, pi. 28, fig. 

 18, 1856. Not of Holmes, Post- Pleiocene Foss., p. 64, pi. x. fig. 7, i860. 

 The shell figured by Holmes is, from his type, a Tritonidea, probably T. 

 cancellaria Conrad, and obviously different from that figured in the earlier 

 work. The present species is well characterized, and no recent representative 

 of it is known in the present fauna. 



Subgenus Trigonostoma Blainville. 

 Trigonostoma tenera Philippi. 

 Plate 10, figure 8. 

 Cancellaria tenera Philippi, Zeitschr. fiir Mai. V., p. 24, 1848. 

 Cancellaria Stimpsoni Ca]k'ms, Proc. Dav. Acad. Sci. II., p. 250, pi. viii. figs. 4, 5, 1878. 



This species, which in the recent state inhabits the Gulf of Mexico, and is 

 represented on the west coast of Central America by C. bnllata and C. 



