60 PK0CEED1NGS OF THE GEOLOGICAL SOCIETY. 



was given by Prof. Cope in 1870 as a character of his genus 

 Elasmosaurus,a, very long-necked Plesiosaurian, to which, as already 



Fig. 16. — Shoulder-girdle of Pliosaurus, Owen. 



pc, the prsecoracoid ; co, the coracoid ; sc, the scapula ; gl t the glenoid fossa ; 

 /, the coraco -scapular vacuity. 



said, Plesiosaurus Manseli, Pies, cliduchus, and Oolymbosaurus seem 

 nearly related. The present untrustworthiness of generic cha- 

 racters of Pliosaurus deduced from the propodial, epipodial, and 

 mesopodial segments of the limbs has already been shown. These 

 and similar delects in regard to the shoulder-girdle do not, however, 

 necessarily annul the genus, which, in spite of them, may survive 

 to afford another illustration of the Linnean aphorism, " Character 

 non facit genus, sed genus dat character." 



The remaining four reptilian papers referred to members of the 

 subclass Dinosauria. Three of these were by Prof. H. G. Seeley. 

 One was a description of a sacrum, represented chiefly by a cast in 

 sandstone, remarkable for the large number (seven) of the vertebral 

 centra composing it, and for the lateral compression and height of 

 the neural canal. The same author, in another paper, brought 

 under our notice some thoracic vertebrae from Wealden rocks, 

 distinguished by the lateral compression of the centrum inferiorly, 

 which suggested the name Sphenospondylus. It is a form of ver- 

 tebra not uncommon at more than one horizon in the Wealden cliffs 

 of the south coast of the Isle of "Wight, from which I have myself 

 dug out several, one of which was associated with an Iguanodont 

 ischium. This and the close resemblance of their compressed 

 figure to that of the centra of the same part of the vertebral column 

 in Iguanodon Prestwichii led me to refer such vertebrae to a species 

 of Iguanodon. The last two papers I shall notice are a description 



