Cretaceous Fossils of Aberdeen. 249 



but only by fragments which prevent a definite determination. 

 Our specimens do not allow us to see so near an alliance with 

 Ammonites Pailletteanus, as Salter and Baily seemed to recognize 

 (Q.J.G.S., vol. xiii, p. 87). 



Ammonites (Hoplites) Mortilleti, Pictet and De Loriol. 1 — Several 

 fragments, and one or two more perfect specimens, indicating 

 Ammonites of from one to two inches diameter, we refer to this 

 species. At first we thought they were A. noricus ; but the 

 ribs upon the back do not tend to meet at an angle as they do 

 in that species. The specimens all seem to show that the shell 

 was compressed to about the same extent as, or even more than, 

 in A. noricus ; that the umbilicus was very open, there being 

 scarcely any overlap of the whorls ; the outer ones doing little more 

 than touch the inner ones. Around the umbilicus the ribs are 

 nodular, and upon the sides they quickly divide into two or three 

 ribs which pass to the back with a slight sigmoid curve ; the curve 

 is probably more marked in larger shells. On each rib, where it 

 bends over to the back of the Ammonite, there is a small but 

 distinct tubercle. The ribs extend a short way towards the middle 

 of the back, and at right angles to it, but a smooth space is left 

 along the middle line. There is no evidence of the ribs upon the 

 back being angulated as they are in Ammonites noricus. This 

 Moreseat Ammonite has some resemblance to Ammonites splendens, 

 but in that species the back is more definitely flattened, the 

 tubercles are really swollen terminations of the ribs, and the 

 umbilicus is very small. 



There is one specimen in Mr. Lamplugh's collection from the 

 upper part of the Noricus beds at Speeton, about one inch in 

 diameter, which we believe to be specifically identical with the 

 form now being considered ; and there is a second which 

 M. Pavlow has referred to A. (H.) Mortilleli. It seems very 

 probable that the two Speeton forms are the same species ; but the 

 one seen by M. Pavlow, which is nearly 1^ inches in diameter, 

 has the tubercles, upon the outer part of the last whorl, placed 

 at irregular intervals. 



Crioceras Duvalii ? — Several fragments, some indicating whorls 

 1^ inches wide, and others much smaller, are doubtless referable 

 to this genus : the large transverse ribs, with several smaller ribs 

 in between them, and the presence on some of the larger ribs of 

 spines, irregularly placed, give to these specimens a strong re- 

 semblance to Crioceras Duvalii; but the evidence is not sufficient 

 for definite determination. 



Belemnites. — Several pieces of Belemnites have been detected, but 

 they are too small and fragmentary for determination ; one may, 

 perhaps, be Belemnites minimus. Mr. Lamplugh, comparing these 

 with Speeton forms, detects nothing that could be referred to 

 Belemnites lateralis, but thinks it just possible one or two may 

 be portions of B. jaculum. 



1 Paleont. Suisse, Neocomien des Voirons, 1858, p. 21, pi. iv, fig. 2. 



