I06 TRANSACTIONS OF THE WAGNER FREE 



shown by Owen's figure. The species has since been collected by the State 

 Geological Survey under Dr. John C. Branner at the same locality and is ac- 

 companied by a species of Macr'on of rather similar external form. Lagena 

 rlwmboidea Gabb (Geol. St. Dom., p. 218, 1873) is, from the types, a young 

 Mazsalind much resembling M. Ozueni, but more slender and with a propor- 

 tionally longer canal. 



Mazzalina costata n. s. 

 Compare Tryon, Struct and Syst. Conch. II. pi. 48, fig. 100. 



As Conrad's type-specimen of M. pyrida has so far remained unique, its 

 limits of variation are uncertain, but in the Miocene of the Chipola River 

 near Bailey's Ferry, West Florida, and in that of White Beach, Little Sarasota 

 Bay, South Florida, is a species which differs from it in the following particulars: 



It is wholly covered with not very prominent, coarse spirals crossed by 

 distinct incremental lines instead of being smooth behind the canal. It has 

 eight or nine wide, rounded, prominent costae, which begin in front of the 

 shoulder and extend forward to the suture, which is undulated by them. It 

 has three strong, continuous plait.s on the pillar, the anterior of which is undu- 

 lated instead of simple on its edge, and two or three supplementary, fainter 

 ridges appear behind the others at maturity. The adult shell has six or seven 

 whorls and the canal is narrower and proportionately a little longer than in 

 M. pynda. The young are more slender than M. pynda, but the adult is quite 

 globose, and the costae are obsolete on the last whorl. The adult measures 

 about 48 X 30 mm. 



My specimens of this form are too fragmentary and imperfect to be suit- 

 able for figuring, but they appear to me to be quite distinct from the Eocene 

 species. 



Genu.s LATIRUS Montfort. 

 Latirus floridanus Heilprin. 

 Plate 8, figure 2. 

 Lath-US floridanus Heilprin, op. cit. p. 108, pi. 15, fig. 42, 1887. 



Miocene silex-beds of Ballast Point. Also in the uppermost Eocene beds 

 (nummulitic) near Martin's Station, east from Tampa. 



This species reaches a length of 55 and a maximum diameter of 23 mm. 

 The aperture, including the canal, reaches a length of 32.5 mm. The whorl 

 slopes up obliquely to and is appressed at the suture ; the spirals are close- 

 set and alternate in size, only one fine one between two coarse ones ; there are 

 nine ribs or costae on the last whorl. There are two obscure plaits on the 

 pillar, not visible from in front and rather weak ; they are close to the anterior 

 edge of the pillar. In fully adult specimens three or four not prominent, 

 somewhat irregular lirae appear on the pillar. The figure, which was taken 

 from a somewhat immature specimen, does not show these, but they are arranged 

 much as in figure 7 on the same plate. The intercalary fine lines were also 



