PALMOZOIC ROCKS IN CANADA AND SCOTLAND. 381 
Fig. 20. Upper portion of jaw oblong and flattened, with six 
faintly marked crenulations; this part extends downwards, forming 
a flattened prolongation, first at right angles, and then nearly parallel 
to the upper part. 
II. Annelid Jaws from the Clinton and Niagara Groups (Silurian), 
So far as my researches have extended, these minute jaws are not 
so widely distributed in the Silurian strata in Canada as in the lower 
strata of the Cambro-Silurian ; but they appear to be abundant in 
the single locality in which they make their appearance. They are 
for the most part closely related to the species already described, 
whilst three forms—LHunicites major, Gnonites inequalis, and Gno- 
mites cuneatus—occur in these as well as in the lower rocks. The 
beds yielding these fossils are shown in the same escarpment—the 
Clinton strata in the lower portion, and about 200 feet higher the 
bituminous shaly bed of the Niagara, these two rock divisions being 
only separated by an arbitrary line in this part of Canada. As all 
the forms described are from Dundas, Ontario, I need only mention 
after the description of each the particular division from which it 
came. 
EVNICITES CLINTONENSIS, Hinde. (Pl. XIX. fig. 21.) 
Jaw elongated, narrow, with a blunted posterior termination, the 
anterior portion elevated and slightly curved inwards, the two 
front teeth rounded and somewhat larger than the rest, followed 
by a series of about fifteen teeth, gradually diminishing in size 
towards the extremity of the jaw; the first two in the series are 
rounded, all the rest are acutely pointed and directed backwards. 
Length 1 line, width + line. 
This form is closely allied to #. perdentatus, from which it may 
be distinguished by its more robust proportions and possessing fewer 
teeth, though nearly double the size. Abundant. 
Clinton formation. 
EUNICITES CoRONATUS, Hinde. (Pl. XX. fig. 9.) 
Jaw somewhat semielliptical in outline and strongly arched, 
blunted at both ends, and having on the upper border about twelve 
rounded teeth, of which the first five are subequal, and the others 
gradually diminish in size. Length # line, depth nearly 2 line, 
Abundant. 
Clinton formation. 
EvnicirEs cuiromorraus, Hinde. (Pl. XX. fig. 10.) 
Jaw forming a triangular plate, with one end pointed and strongly 
incuryed ; beginning at the opposite end there is first on the upper 
border a series of five very large blunted upright teeth, and succeed- 
ing these are five very small teeth or crenulations, Length 3 line, 
width 3 line. 
Clinton formation, 
