G. F. Matthew—The great Acadian Paradouwides. 3889 
almost complete example has lately been found, from which it 
appears that the species differs from any hitherto described. 
Its nearest allies are P. Bennetttd of Newfoundland and P. 
Harlani of Massachusetts, but it has not the “ pendent ears” 
and abortive spine of the former, nor the long (sometimes ex- 
travagantiy long) spine and round pygidium of the latter. It 
has a rather smooth test, and the eye-lobes are shortened and 
placed as in the two species named. It differs from P. Bennettir 
in being brachypleural in the adult stage, and from P. Harlani 
in having only seventeen segments in the thorax. It may be 
described as follows :— 
PaRADOXIDES REGINA. 
A species of the largest size and having a very wide body. 
Head shield greatly expanded, and having the genal angles 
produced into short spines; glabella broad and possessing two 
complete furrows; eyes 
rather short, situated oppo- 
site these furrows. Thorax 
with seventeen joints; hav- 
ing the axis very broad, 
and the ends of the pleura 
leaf-like, curved, but scarce- 
ly reflected, and having the 
three last joints shorter 
than the others. Pygidium 
subquadrate behind, with 
a small axis and with the 
lateral lobesex panded back- 
ward. Hzypostome subquad- 
rate behind, but having the 
posterior angles truncated, 
anterior lobe widely ex- 
panded laterally, and hav- 
ing the anterior margin 
expanded and widely ex- 
tended. 
The specimen is defective where the two anterior. glabellar 
furrows would come, and so it is not known whether these are 
present or absent. The horizon is Band 1c of the St. John 
group. This species appears to be the largest trilobite which 
has so far been found in any country, being fifteen inches long 
and twelve inches across the cephalic shield. Professor W. C. 
Broégger calculated the length of an example of Megalaspis 
acuticauda found in Norway as sixteen inches (403™™), and the 
late M. Barrande gave the length of Asaphus Barrandei, found 
in France, as fifteen and a half inches (400™™), but these larger 
Asaphi are narrower in proportion than the Acadian trilobite. 
