384 The Rev. W. D. Conybeare on the Discoveri/ of 



intimately allied to the tortoise ; and decidedly connect it with the Saurian 

 order. 



It will be necessary to subjoin a few words on the inferior hatchet-shaped 

 processes which may be seen depending on either side from the lower part 

 of the cervical vertebrae. Most animals present traces of these processes ; 

 they are particularly prominent in many of the long-necked quadrupeds, and 

 in birds project into a long styloid branch : a rudiment of these may be 

 observed in man, but I am not aware that any particular name has been 

 assigned to them*. They have been sometimes confounded with the trans- 

 verse processes, to which they often form a wing-like appendage. These 

 processes are important, as serving to determine the number of the cervical 

 vertebrae, and as affording very close analogies between the plesiosaurus and 

 the crocodile ; in both these animals these inferior hatchet-shaped processes 

 are exactly similar in figure, and form separate pieces attached to the body of 

 the vertebrae by a double stem : in the figures given of the cervical vertebrae 

 in my former memoir, this stem alone and the double suture which receives 

 it, could, from the imperfect state of the specimens, be represented ; but 1 

 then expressed my conviction that the structure resembled that of the same 

 part in the crocodile, and my conjecture is now verified. 



The thirty-five anterior vertebrae of the plesiosaurus exhibit these processes 

 distinctly characterized, and are therefore beyond all doubt cervical ; in the 

 six following the processes become lengthened, and gradually lose their 

 hatchet-shaped extremity, assuming rather the form of false ribs, and should 

 therefore perhaps be classed as anterior dorsal ; but the whole forty-one are 

 clearly placed before the pectoral extremities. In the crocodile there are 

 seven cervical vertebrae with hatchet-shaped processes, and three anterior dor- 

 sal with false ribs before the humero-sternal portion. 



Since flexibility must evidently be the end of this great multiplication of 

 the joints, it may perhaps excite surprise that the joints, instead of articulating 

 as in birds by cylindrical surfaces, should have their contiguous faces nearly 

 flat, which must have allowed a less freedom of motion between each vertebra : 

 but it may be answered, that the increased number of the joints compensated 

 for the stiffness of each. 



Dorsal VcrtebrcE. — I have nothing to add to my former remarks on this part 

 of the column : the greater part of these, in the splendid specimen from Lyme, 



* Dr. Macartney in his Anatomy of Birds says, " The transverse processes of the vertebras of 

 the middle of the neck spread forwards, and send down a styloid process of some length." — "The 

 anterior styloid processes are bnt little observable in the rapacious and passerine tribes, the par- 

 rot, &c., but they are very marked in the long. necked birds." 



