41 



PhRjVgmoceras parvum, Hall and Whitfield. 

 Plate 7, flg. 2. 



Phmgmoceras parmm, Hall and Whitfield. 1875, Pal. Ohio, vol. 2, p. 151, pi. 8 



fig. 10. 



Two imperfect casts of the chamber of habitation of a Phragmoceras 

 have been collected at Hespeler, which resemble P. parvum in their 

 small size and in the tubular prolongation of the ventral end of the 

 aperture. These specimens appear to differ from the type of that 

 species only in not being quite so much curved. 



ASCOCERAS TOWNSENDI. (N. Sp.) 

 Plate 6, figs- 4 and 4a. 



Shell small, slightly compressed at the sides, regularly oval in trans- 

 verse section, its septate portion conical and widening gradually as 

 well as somewhat convexly upwards from an obtusely pointed base : 

 chamber of habitation unknown, with the exception of a small portion 

 of its decurrent extremity : test and surface markings of the test also 

 unknown. Septa apparently three in number. The first or posterior 

 septum crosses the dorsum at a distance of about one millimetre from 

 the posterior end, then curves concavely upwards on each side and 

 finally passes over the ventral edge at a distance of eleven millimetres 

 from the posterior end. The second septum crosses the dorsum close 

 to the first and runs closely pai-allel with it on each side in its upward 

 and concave curve, after which it bends first convexly towards the 

 dorsum, and then suddenly backwards towards the ventral edge, which 

 it ultimately passes over at a distance of four and a half millimetres 

 above the septum. On the immediate centre of the dorsum the third 

 septum is about one millimetre distant from the second : then for some 

 distance on each side, as far as the upward concave curve extends, the 

 sutui-es of the third and second septum are confluent, after which the 

 third septum also bends convexly towards the dorsum, and then rather 

 abruptly backwards towards and to the ventral edge, which it finally 

 crosses at a distance of four millimetres above the second septum. The 

 siphuncle is visible only at the pointed or posterior end : it is veiy 

 small, and at this point is situated close to the centre of the dorsal 

 margin of the first air chamber. The ventral half of the first air 

 chamber is marked by a transverse groove or constriction. 



Durham, Mr. J. Townsend, 1883 : a well preserved cast of the septate 

 portion of the shell, with a small portion of the decui-rent posterior 



