268 C. H. HURST, PH.D. 



"counterpart." Whether this really shows that the vertebrae (of the 

 tail) were mainly cartilage or other soft tissue with only a crust of 

 bone or not, may be open to question. The perfectly-fitting joints, 

 the large transverse processes of the anterior caudal vertebra, and the 

 slenderness and stiffness — as shown by the straightness of the tail in 

 both specimens — of this region of the vertebral column are strong 

 evidence that the bones were well-ossified. 



Of the nine cervical vertebrae, only eight are well-preserved, the first 

 being almost unrecognisable. Measuring the lengths of the centra of 

 these on a large photograph (scale yff-)> I make the sum of the eight 

 in the Berlin specimen to be about 75 mm.; but Professor Dames 

 gives numbers which together make only 60*5. A glance at Plate XV. 

 will show the position of the neck in this specimen. It is very 

 strongly arched so as to bring the head almost into contact with the 

 back of the animal in the region of the thorax. It is difficult to make 

 these measurements accurately in either the specimen or the photo- 

 graph, but the discrepancy between the two measurements is too 

 great to be accounted for by this difficulty, and I suspect that Professor 

 Dames' measurements have been made along the inner curve — i.e., 

 through the neural spines — while mine were made near the ventral 

 curve, i.e., through the centra of the vertebrae. I suspect, therefore, 

 that when the animal's neck was straightened out it would be 75 mm. 

 long in addition to the length of the atlas, which may be taken to be 

 a very small quantity as in modern birds. Of the nine cervical 

 vertebrae the middle ones are longer than those nearer the ends of the 

 neck, the fifth being the longest. 



Cervical ribs, apparently movably articulated, may be made out, 

 and there appear to be eight pairs of them. The neural arches and 

 spines are well-developed and strong, the spines being 2 to 3 mm. high. 



The trunk vertebrae being somewhat displaced, and the vertebral 

 column distorted, it is not very easy to make sure of their number. 

 There appear, however, to be ten, measuring together about 70 mm. 

 The vertebrae appear to be almost equal in size, and nine of them bear 

 ribs. There are also ventral ribs, resembling the " abdominal " ribs of 

 the geckos and chamaeleons, and clearly showing the ventral boundary 

 of the abdominal cavity (see 14 in Plate XV.). 



The sacrum is hidden in the Berlin specimen except at its ends. 



