AND CLASSIFICATION OF THE FOSSIL KEPT I LI A. 
211 
condyles. The second segment of the limb is more like that of a Dinosaur than any 
other animal. Very few Dinosaurs have the tibia and fibula as long as the femur, 
but Professor Marsh has figured this condition in Laosaurus; and in Compsognathus 
the relative elongation of the second segment of the limb is greater than in Protoro - 
saurus. Ornithosaurs also have this segment of the limb the longer, but then the 
fibula is only developed proximally, as among Birds. The proximal expansion of the 
tibia in Protorosaurus and its cnemial crest, well seen in the type specimen, are 
typically Dinosaurian (fig. 4). The sigmoid flexure seen in the fibula in some examples 
of Protorosaurus suggests that the bone terminated distal ly in front of the tibia, as in 
Archaeopteryx and certain Dinosaurs. 
The tarsus differs from that seen in Dinosaurs in some important particulars. 
First there is a large astragalus which appears in the Swedenborg specimen to have 
an ascending talon ; then there is a compressed calcaneum, which in the Waldenburg 
specimen articulates with the cuboid bone. Between this proximal row and the 
distal row of three cuneiform bones are the cuboid and naviculare. This remarkably 
well developed tarsus is distinctive of Protorosaurus, and Mammalian in its elements. 
There are five stout metatarsals, which increase in length from the first to the 
fourth, while the fifth is but little longer than the first. They do not decrease in 
stoutness, as is the case with Crocodiles. They are more elongated than among Lizards, 
though Scaphceosaurus has similar bones, but shorter than in Compsognathus and 
some Ornithosaurs, like Dimorphodon. No near parallelism is possible with Dinosaurs, 
because the bones of the digits are so greatly elongated in Protorosaurus , for this 
condition gives a Lacertilian character to the hind-limb, though the stoutness of the 
phalanges and metatarsals is more Dinosaurian. From the shortness of the first and 
fifth digits, and especially of the metatarsals of those digits, the foot has a suggestive 
aspect of degeneration, which, when the metatarsals came to be carried in an elevated 
position, might result in the development of such a foot as is seen in Allosaurus, 
though the fact that the fourth metatarsal is the longest seems to offer some difficulty 
in the simplification of the Protorosaurian foot. The digital bones are ossified on the 
Dinosaurian type. 
The shoulder-girdle and fore-limb. —The shoulder-girdle is less perfectly 
preserved than the pelvis. Bones which I regard as the coracoid and scapula aie 
preserved in the Munich specimen. If these are traced off’ and articulated, they show 
that the coracoid was relatively large, but, like the scapula, is suggestive of Dino¬ 
saurian or Ichthyosaurian form, though the coracoid is not without some resemblance 
to the bone in Plesiosaurs, and Plesiosaurs always want the narrow anterior notch. 
Only a trace of these bones is seen iu the Vienna specimen, where the very 
imperfect coracoid and scapula appear to have had similar forms ; but there is no 
evidence whether the coracoids met in the median line, or whether other bones 
* Yox Meyer, ‘Fauna der Vorwelfc,’ “ Rapfcilien aus dem LitTograpliiscben Scliiefer dos Jura,” t. xiii, 
