106; ON THE STAGONOLEPIS ROBERTSONI AND THE 
responds with the centre of each scute, in a fine specimen of a frag- 
ment of the ventral shield of Zeleosaurus Cadomensis (32,591 B.M.). 
The external scutes on each side are somewhat bent up towards the 
dorsal surface ; but in this, as in other specimens, the outer margins 
of these scutes thin out, and exhibit not the least sign of having been 
connected with any other. In this respect there is a marked contrast 
between the outer and the inner edges. 
There are six longitudinal rows in this specimen, which is the 
number assigned by Geoffroy St.-Hilaire (supra, p. 103) to the Teleo- 
sauria generally. Six exist, as we have seen, in 7. dcemporalis. 
Dr. Wagner found only five in his specimens of the ventral shield 
of 7. Cadomensts ; but, as he states, it was imperfect. Six are, as I 
have pointed out, represented by Cuvier in 7. Cadomensis, and the 
same number is shown in the figure, given by Bronn and Kaup, of 
Pelagosaurus typus. These authors state that there are ten longi- 
tudinal rows of scutes in the dermal armour of .J/ystriosaurus longtpes ;, 
but their figures and description make me think that this is a hypo- 
thetical conclusion, and that what they have seen and figured is only 
the ventral armour, with its six rows of plates. 
I cannot ascertain from Professor Owen’s description what is the 
precise number of longitudinal series of “lateral and ventral” scutes. 
in TLeleosaurus Chapmannt, They are said to be “more perfect 
squares than those next the spine,” and to have no keels. In these 
respects they obviously agree with the corresponding scutes of the 
Teleosaurta ; but it is stated that “the median abdominal scutes are 
not opposite but alternate; their median margins are rounded off or 
slightly angular; and, while the anterior part of that margin is over- 
lapped by the posterior half of the opposite scute in advance, the 
posterior half overlaps the succeeding scutum of the opposite side.” 
This description would apply much better to the sutures between a 
median series and that which follows it externally, than to the 
junction between the two median series of ‘scutes, which are always 
opposite in the Zeleosaurza I have examined. 
The internal faces of the dorsal scutes of the TZeleosauria are 
concave from side to side, and convex from before backwards; they 
may be smooth or carinated, but the ventral scutes appear to be 
always flat and without a keel. 
Comparison of the Scutes of Stagonolepts with those of Crocodtlia 
and Teleosauria.—Bearing in mind the features of the dermal armour 
of the Crocodzlza which have just been detailed, it becomes no difficult 
matter at once to find an analogue for each kind of scute found in 
Stagonolepis. The flat scutes are strictly comparable to those of the 
