672 SILURIAN TRILOBITES OF NEW SOUT'.i WALES, V.. 



(6) the backward and inward situation of tlie eyes; and (7) the 

 manner in which the axial furrows bifurcate outward and inward 

 on reaching the frontal borders of the free cheeks. 



So different are the posterior branches of the facial sutures of 

 this species, in more than one particular, we are rather inclined 

 to the opinion that in this fossil we have a new genus. 



Besides the portions above-described, several pygidia were 

 found associated with them, which may or may not prove to 

 belong to the same species; and because of their association and 

 dissimilarity to all other pygidia, it is not unreasonable to assume 

 that they probably do. They will be described separately. 



Log. arid H or. — -Near Duntroon Homestead, Parish Canberra, 

 County Murray, N, S. Wales. Upper Silurian!/?). Coll. Mitchell. 



vii. PORTIONS OF ENCRINURL 

 1. Cephala. 



a. — Portion of a single cephalon (PI. Ivi., fig. 7) differs from all 

 the others described ante, in the form and proportions of the fixed 

 cheeks. The entire shield is unknown, but pr«>bably possessed 

 a subsemicircular outline. It is strongly inflated and granulate 

 on all parts preserved. The pyriform glabella is very convex 

 and bold anteriorly, the neck-ring narrow but distinct and much 

 arched, but the neck-furrow narrow and shallow. The features 

 which distinguish this cephalon are the form of the fixed cheeks, 

 position of the eyes, and the course of the facial sutures. These 

 latter, between the eye-position and the lateral borders of the 

 cephalon, are straight, i.e., practically parallel to the neck seg- 

 ment, with the result that the fixed cheeks, instead of being 

 sublunate in some degree or other, as in most of our E7icrinuri, 

 are more or less parallelograraatic, the facial sutures cutting the 

 lateral borders some distance in advance of the bluntly rounded 

 genal angles. The eye-positions are close to the axial furrows, 

 and as between anterior and posterior, almost median. The 

 fixed cheeks also appear to be much more inflated than ordin- 

 arily. We are not able to associate this specimen with any of 

 the preceding reiniins, but found in company with pygidia de- 

 scribed later on, and a Brachiopod resembling Meristella tumida. 



