471 



interest to merit special mention. In line with the cephalic demi- 

 facets, and, therefore, presumably in the position in which the caudal 

 facets would occur were they present, there are rounded, projecting 

 thickenings of the epiphyses fitting into notches in the centra (Fig. 1 *), 

 On examining the vertebral surface of the ejjiphysis, it is found that 

 these projections occur at the most ventral and lateral ends of those 

 ridges to which Albrecht^) gave the name of Crista centro- 

 n ear alls. A similar conformation is present in the first three lum- 

 bar vertebrae. Although Albrkcht has figured and described the 

 epiphyses in Ursus arc tos, he does not seem to have found the 

 condition here mentioned. That the curious expansion of the caudal 

 epiphysis is not confined to the lion, is shown by the examination of 

 the vertebrae of young domestic cats, where the same feature may be 

 seen. It seems possible that here is a peculiarity of the Felidse not 

 shared in by the Ursidse. 



If the interpretation of these projections as serially homologous 

 with that part of the epiphysis from which the demi-facets are formed 

 be correct, then they are equivalent to Albrecht's "Ka tap op hy sen- 

 flüg el", which, therefore, in the last four thoracic vertebrie become 

 more lateral in position, and coincide with the lateral part of the 

 neuro-central synchondrosis. Furthermore, it is to be noted that the 

 crista, from being practically horizontal (in the standing position of 

 the animal) in the tenth vertebra, becomes gradually more and more 

 oblique in the last three thoracic and in the lumbar vertebrae. That 

 is to say, taking the crista as indicating the position of the neuro- 

 central synchrondrosis, the ossific centres for the neural arch form a 

 greater and greater proportion of the vertebra; thus gradually ap- 

 proximating the condition in the sacrum ^) 



Lumbar vertebrae. The spinous processes are similar to those 

 of the thoracic vertebrae. The mammillary processes are completely 

 ossified. The tips of the accessory processes of the first vertebra are 



1) P. Ai BRECHT, Die Epiphysen unci die Amphiomphalie der 8äuge- 

 tierwirbelkörper. Zool. Anz., Bd. 2, 1879. 



2) The second thoracic vertebra of lion No. 1 has a double ce- 

 phalic articular process on the left side. The additional articular sur- 

 face is medial in position; almost reaches the middle line, and is about 

 half the size of the lateral facet. A narrow non-articular interval se- 

 parates the two articular surfaces. From a comparison with the normal 

 process of the same vertebra of lion No. 2, it is evident that the lateral 

 facet represents the normal articular process. On the left side of the 

 vertebra the articular surface is larger than usual ; extends nearer to 

 the middle line, and is crossed near its medial end by a shallow narrow 



