208 Mr. Owen on Fossil Remains from the London Clay. 



small Turkey-Vulture (Cathartes aura), for example, besides the same general form 

 and proportions of the bones, so far as they exist in the fossil, we have the same 

 degree of development, and the same direction of the intermuscular ridge on the 

 under surface of the sternum, which divides the origins of the great and second 

 pectoral muscles. The outer angle of the proximal end of the coracoid is produced 

 in the same degree and form, and a similar intermuscular ridge is present on the 

 anterior and towards the outer part of the coracoid. The preserved extremities of 

 the femur and tibia have the same conformation and relative size in the fossil as in 

 the existing Cathartes. In this genus, nevertheless, there is a deeper depression 

 on the outer surface of the sternum, external to the coracoid groove, than in the 

 fossil, but this difference is less marked in some of the larger Vulturida. The fossil, 

 moreover, indicates a smaller species of Vulturine birds than is known to exist in 

 the present day, and probably belonged to a distinct subgenus. 



The professed ornithologist may receive with reasonable hesitation a determina- 

 tion of the family affinities of an Ornithic fossil arrived at in the absence of the 

 usual characters afforded by the beak and feet ; but the comparisons instituted 

 in reference to the present fossil have established so many unexpected points of 

 difference and resemblance, as to embolden me confidently to anticipate, in the 

 event of the subsequent discovery of the cranium and mandibles, the bones of the 

 extremities, or the entire sternum, that they will establish the conclusion that the 

 Sheppey Ornitholite is referable to a member of the group of Accipitrine Scaven- 

 gers which are so abundant in the warmer latitudes of the present v/orld. 



The Ornitholite in the museum of Mr. Bowerbank consists of ten sacral vertebrae 

 anchylosed together, as is usual in Birds, with a continuous, keel-like, spinal ridge; 

 four of these confluent vertebrae are analogous to the lumbar vertebrae in the Mam- 

 malia, and they are succeeded by five others, in which, as in the Vultures, the in- 

 ferior transverse processes are not developed ; this character is, however, by no 

 means peculiar to the Vulturidce. The part preserved in the fossil, though emi- 

 nently characteristic of the class of birds, is not one which is calculated to throw 

 light on the closer affinities of the species to which it belongs. 



For the species of Vulturida indicated by the above-described fossils, the name 

 of Lithornis vulturinus may be provisionally given. 



PI. XXI. 



Fig. 5. Front view of the Hunterian Ornitholite. 

 Fig. 6. Side view of the same, of the natural size. 



