41 
The shape of the head of E. Earrandei has much agreement with that 
of E. pimctatus’, it is however, a little broader, the glabella is much less 
convex, the axal furrow is faintly marked ; I have not succeeded in deter- 
mining the presence of glabella furrows. The genal spines are almost 
altogether wanting. The tubercles, with which nearly all the surface is 
covered, resemble much, both in form and general arrangement, those of E. 
punctatus, but appear to me to ])e less numerous on the fixed cheeks. The 
eye is small, flat, and little raised above the surrounding surface, it is facetted. 
Opposite the centre of the palpebral lobe, and a very little distance from it, 
may be seen a tubercle, which is a little larger than those surrounding it. 
The pygidium is sub-triangular and a little broader than long, while 
the opposite obtains in E. pimctatus. The angle formed by the sides at the 
extremity instead of being acute as in the last-mentioned species is obtuse 
and nearly a right angle. The axis is made up of twenty-five or twenty-six 
segments distinct throughout and non-tuberculate ; the lateral lobes are much 
wider than the median, and are made up of nine arched ribs, more or less 
inclined according to the position they occupy. These ribs are quite smooth, 
and are separated from one another by a shallow furrow ; the posterior 
extremity of the pygidium shows no sign of a spine. 
Eimensions. — Length of the head, thirteen millimetres ; breadth, 
twenty-eight millimetres ; distance between the eyes, eleven millimetres ; 
length of the pygidium, thirteen millimetres ; vridth of the first segment of 
the axis, five millimetres ; width of the first rib, 7 '5 millimetres ; angle of 
the posterior extremity, about 100°. 
Eelations and Eifferences. — As I have already observed above, this 
species occupies a position midway between E. punclatus and variolarls. As 
I have already laid stress on the characters which distinguish it from the first- 
named, I will now confine myself to those which separate it from the second, 
as well as from E. sexcostatus, Salter, and multiser/mentatus, Portlock. I 
have remarked that the head, and particularly the glabella of E. variolaris, are 
more inflated and more convex, and that its eyes are more prominent ; and, 
moreover, the axis of the pygidium is composed of ten segments, according to 
Pletcher, and of from nine to twelve, according to Salter. The small number 
of pygidial ribs in E. sexcostatus, coupled with the convexity of its glabella, 
serves to obviate confusion with E. Earrandei. As to E. multisegmentatus , 
it differs from it in the more triangular and narrower form of the head, and 
in the greater number of segments of the axis and ribs in the pygidium. 
