508 



THE SKULL OF BRANCHIOSA URUS. 



salamanders, especially the young forms, in possessing gills ; and in 

 the broad head rounded in front, the short thick well-developed 

 extremities terminating in digits, and in the rudder-like tail which 

 strongly suggests the larval forms of living Urodela. The skin was 

 dense, and its impression is preserved and shown in the figure. The 

 form of the skull will be gathered from the figure, 142, in which 

 Professor Fritsch has restored the upper surface of the skull of 

 tiranchiosaurus, enlarged six times. The lettering indicates the same 



Fig. 142. 



bones as in the skull of Dolichosoma. There are about 20 vertebrae 

 in the neck and back, and 21 in the tail. 



Dolichosoma longissimus (Fritsch) may serve as another type 

 of amphibian structure. It is described by Professor Fritsch as dis- 

 tinguished by having the ribs twice as long as the vertebrae. In form 

 it closely resembles the whip-snake (DendropMs). The fragment 

 found measures 60 cm., and indicates for the entire animal a length 

 of about a metre. An impression of the skin is preserved ; enlarged 

 45 times it shows a fine granular structure, so that if any scales existed 

 they are not preserved. 



The eyes are placed rather behind the middle line of the skull, 

 and are separated by an interspace of two-thirds their diameter. The 

 parietal foramen (Pa) lies far behind the orbits. The anterior nares 

 cannot be distinguished. The nasal bones (N) are anchylosed toge- 



