156 



FOSSIL BIRDS. 



The following table shows the number and order of articula- 

 tions in the various reptiles : — 



Land tortoise 



Marine tortoise 



Crocodile 



Lizards of all species 



Cameleons 



Seps tetradactylus . 



Seps tridactylus 



Frogs, toads, &c. 



Salamanders 



. 2. 2. 2. 2. 



2. 3. 3. 3. 2. 



2. 3. 4. 5. 



2. 3. 4. 5. 3. 



1. 2. 3. 3. 2. 



2. 4. 5. 2. 

 2. 3. 4. 



2. 2. 3. 4. 3. 



2. 3. 3. 2. 



Thus we see that in the crocodile alone the number of arti- 

 culations are the same as in the birds ; but as each of their 

 toes is supported besides on a particular bone of the metatarsus, 

 there can be no mistaking the foot of one for that of the others. 



Now, all the different feet in the ornitholites examined by 

 the Baron had precisely the characters we have just instanced 

 as belonging to the birds. In one of the feet we mentioned 

 above, the thumb was wanting, but the httle supernumerary 

 bone which supports it in many birds was observable. In 

 another specimen these characters were still more complete; 

 the femur was wanting, but the tibia was more entire, and the 

 thumb and three other toes are very complete, and provided 

 with their entire number of articulations. 



In another specimen belonging to the Baron, the tibia and 

 tarsus were rather longer than in the last. Feet of a similar 

 description are very common in the gypsum, and seem to be- 

 long to a different species. 



A third species is indicated by a foot about the same size as 

 the last, but in which the bone seems thicker, and the tarsus 

 more arched in its length. In other respects it has all the cha- 

 racters of the genuine foot of a bird, except that the external 

 toe having left but a single print of its upper part, the three 

 articulations of which it should be composed are not well dis- 

 tinguished. 



To a fourth species belonged the foot, which wc mentioned 



