94 INFERIOR OOLITE AMMONITES. 



but it cannot be regarded as common. In Gloucestershire Mr. "Witch ell found 

 some medium-sized examples in the Gryphite-grit of Frith Quarry, near Painswick, 

 and of Rodborough Hill, near Stroud. 



Plate XVI, fig. 1, representing the type form of this species, is a fine adult 

 specimen, the largest I have seen, having part of the body-chamber present, and 

 the test very well preserved. Fig. 2 shows the front view, with the flat ventral 

 area and large prominent carina. Figs. 3 and 4 illustrate a smaller specimen of 

 the size more usually found, showing the transition from ribs to almost entire 

 smoothness. Some portion of the body-chamber is present, and its continuation 

 onwards is indicated on the specimen, as may be seen in the figure. Both these 

 specimens were collected by my father. Figs. 5 and 6 show a very good specimen 

 with its test very well preserved. This is a form with wider umbilicus. It has 

 no portion of the body-chamber, and is more compressed. It is from Bradford 

 Abbas, and was collected by myself. Figs. 7 and 8 give a smaller specimen, 

 having the commencement of the lateral process, which, however, is not too well 

 preserved, and is, perhaps, drawn a little too broad. The rest of the test is well 

 preserved, and shows the nature of the ribbing. Fig. 9 is a smaller specimen, 

 which shows how the plain and almost straight ribs gradually become more bent. 

 Figs. 10 and 11 depict a young specimen of the narrow-umbilicate and somewhat 

 thicker form. These specimens are not localised ; but they were all collected by 

 my father, probably at Bradford Abbas; they are now in my cabinet. The 

 fig. 24 on Plate A gives the suture-line of this species, taken from the other side 

 of the large type specimen (Plate XVI, fig. 1). It will be noticed that all the 

 saddles are rather broader, and the lobes rather shorter, than in the other suture- 

 lines of the genus. There is also a very considerable development of small lobes 

 in the siphonal saddle. 



Specimens of this species have been in my cabinet for some years, ticketed 

 with the specific name now proposed, and which was given in compliment to my 

 friend Mr. J. F. Walker, M.A., F.G.S., &c. 



Hypbrlioceras discites (Waagen). Plate XVI, figs. 12, 1 3 ; Plate XVII, figs. 1 — 5 ; 



Plate XVIII, figs. 1—5; Plate A, fig. 23. 



1867. Ammonites discites, Waagen. Zone des Ammonites- Sowerbyi, Geogn. 



palaont. Beitrage, pi. 28 (5), figs. 2 

 a, b. 



Discoidal, compressed, strongly carinate ; whorls flat, broad, with their sides 

 nearly parallel, ornamented in youth with sub falciform radii, which become 

 ribs on the outer lateral area, and change sooner or later, according to the 





