ON THE DERMAL ARMOUR OF CROCODILUS HASTINGSLE 167 
the sides, or, in other words, angulated. The s¢rovgly angulated 
articulated scutes (figs. 1 and 2) have the greater part of their posterior 
margins nearly parallel with the anterior, and one lateral margin 
is straight and provided with irregular serratures for sutural union 
with another scute. The other lateral margin, on the contrary, is 
rounded off into the anterior and posterior margins, and ends in a 
thin smooth edge, which has evidently lain free in the dermis. The 
ridge is but little developed in these scutes, and lies over the line 
of angulation, on the outer side of the median line. 
The slightly angulated articulated scutes are, when large, broader 
than they are long (figs. 3, 4, 5). Their four margins are nearly 
straight, though the posterior may be a little convex backwards, and 
both lateral margins frequently, but not always, present sutural 
serrations. The ridge is rather on one side of the middle line, of 
tolerably equal height throughout, and reaches, but does not project 
beyond, the posterior margin. <Anteriorly, it attains the posterior 
margin of the groove which separates the articular facet from the 
rest of the scute. 
From these scutes, which attain a width of 2} inches and a length 
of 2 inches, and often have a trapezoidal rather than a rectangular 
outline, there is a gradual transition down to scutes of an inch in 
length. With this diminution in size there are perceptible differ- 
ences in form, the smaller scutes tending to have the figure of longi- 
tudinally elongated parallelograms, acquiring proportionally more 
prominent ridges and having the posterior end of the ridge more 
produced beyond the posterior margin, which itself becomes more 
convex (fig. 5). 
The angulated scutes without articular facets differ from those 
first described mainly in the fact of the absence of these facets, but 
they are in addition, on the average, smaller, coarser, and more 
irregular (figs. 6 and 7). 
The only unquestionable flat scutes I have seen (figs. 8 and 9) are 
remarkable for the roundness and less regularly radiating arrange- 
ment of the pits upon their outer surface. The anterior edge of the 
scute is straight, thicker than the other, and suturally serrated; of 
the lateral margins, one is straight and without any definite evidence 
of sutural notches, the other is rounded off into the posterior margin, 
which is slightly convex. 
I believe that this scute is imperfect, having lost that anterior 
articular moiety which I have shown (On the Dermal Armour of 
recent Crocodilia: Proc. Linn. Soc. 1859) to be a distinct piece in the 
ventral scutes of the modern Cadman and /acare. In fact, I have 
