INSTITUTE OF SCIENCE, PHILADELPHIA. I O/ 



very faint on this specimen and the draughtsman has not brought them out. 

 One fine thread should appear between each pair on the figure, though these 

 are so fine that in a drawing of the kind used here they would hardly be per- 

 ceptible. 



Latirus (floridanus var. ?) multilineatus Dall. 



Ballast Point silex-beds. 



This form differs from the type in being larger and stouter, in having ten 

 or eleven costs on the last whorl, and in having two or three very fine spirals 

 between every two coarse ones on the last whorl. The apex is shorter and 

 very acute. Lon. 57.0; lat 27.0 mm. It has eight whorls like the type, and 

 in other respects resembles it. 



Latirus rugatus n. s. 

 Plate 8, figures 6, 7. 



Ballast Point silex-beds, Dall & Burns. 



Shell with eight whorls and generally resembling L. floridanns, except in 

 the following particulars : It is considerably smaller, with the same number of 

 whorls ; the whorls are more inflated and rounded instead of sloped to the 

 suture behind them ; on the early whorls (except the nucleus, which is smooth) 

 a prominent spiral marginates the suture ; the costae are more prominent and 

 extend farther either way from the periphery ; the lines of growth are more 

 prominent; the primary spirals are stronger and more distant, at the 

 beginning of the last whorl there are six in L. rugatus, as against 

 twelve in L. floridanus ; the canal is more recurved and more constricted 

 at its junction with the aperture ; the lirse are stronger, and that at 

 the posterior commissure on the body is much stronger than in L. floridanus. 

 Lon. 37.0; max. diam. 18.0; lon. of aperture 20.0 mm. 



This is probably the form referred to by Heilprin as a variety or possibly 

 distinct species from L. floridanus (op. cit. p. 106). It is extremely closely 

 related to a West Indian form usually referred to L. brevicaudatus. 



Latirus callimorphus n. s. 

 Plate 8, figure i. 



Ballast Point silex-beds, rare. 



Shell thin, stout, with seven whorls ; sculptured with ten transverse costte 

 or short riblets confined to the periphery, and close-set, prominent incremental 

 lines ; spirals close-set, alternate, of three sizes ; the primaries and secondaries 

 on the last whorl not very different in size, but simple, the tertiaries very 

 fine and reticulated by the lines of growth ; the tertiaries hardly visible 

 on the upper whorls ; suture appressed, the whorl flattened and sloping 

 in front of it; pillar with two or three obscure plaits hidden within the 

 aperture ; there is no ridge on the body at the commissure; canal short, wide, 

 recurved. Max. diam. 20.0 ; lon. 41. 5; lon. of the aperture, including the 

 canal, 23.0 mm. 



