]86 Annals of the Carnegie Museum. 



A small species, attaining a total length of about 20 cm., and dis- 

 tinguished from all others belonging to the same genus by its slender 

 and elongated form of body, and by the more anterior position of the 

 dorsal fin, which arises opposite the pelvic pair, and does not extend 

 back of a point midway between them and the insertion of the anal. 

 Length of the head with opercular apparatus exceeding the maximum 

 depth of the trunk, and contained about five times in the total length 

 of the fish. Vertebrae about fifty in number, with strong neural and 

 haemal spines. A single large ridge-scale at the upper and lower 

 borders of the caudal pedicle. Teeth small and conical. All fins 

 relatively small, caudal lobes not much expanded. Scales indis- 

 tinctly shown. 



One of the halves of the counterpart in which this specimen is con- 

 tained is illustrated in the accompanying plate, the original drawing 

 having been made by Mr. Sidney Prentice. Within the abdominal 

 cavity, or more particularly, within that part of it lying between the 

 paired fins, is to be seen a tolerably distinct impression of a small 

 reptile resembling a Lacertilian, the precise nature of which is in- 

 determinate, but very probably is akin to Ilomccosaitrus. Only the 

 head and anterior position of the vertebral column are clearly recog- 

 nizable, and it is noteworthy that the creature appears to have been 

 swallowed tail foremost, whereas in the first described specimen the 

 position of parts is reversed. The size of the ingested remains is 

 practically the same in the case of both specimens. 



So far as the present writer is aware, these two are the only instances 

 afforded by paleontology where fossil reptiles happen to have become 

 preserved within the abdominal cavities of fish. These occurrences 

 are all the more remarkable, when it is remembered that the contained 

 reptiles were terrestrial, and their ichthyic foes marine in habitat. 

 This apparent anomaly may perhaps be accounted for by supposing 

 the primitive lizards in question to have inhabited the shores of coral 

 islands in the late Jurassic sea, which covered central Europe at the 

 time. One may suppose the prey to have been captured in proximity 

 to land, or possibly the terrestrial creatures were carried out to sea by 

 floating vegetation to which they had clung, and were seized at a dis- 

 tance from land. The latter hypothesis finds perhaps a certain degree 

 of plausibility from the abundance of plant remains which are known 

 to occur at the Cerin locality. 



The two specimens which are described and portrayed in the present 



