8 
MUSEUM BULLETIN NO. 20. 
striae, however, are grouped in bundles separated by deeper 
furrows, thus giving the surface a decided rugose appearance. 
The character of the surface integument cannot be determined, 
owing to the poor state of preservation. 
Conularm ? sp. 
Plate II, figure 5. 
One specimen is doubtfully referred to this genus. From 
the apex it broadens greatly, having a width of 4 cm. at a 
length of 5 cm. along the mid-line. The sides approximate con- 
verging arcs of eccentric circles. The concentric plates are a 
little more than 1 mm. wide, overlap consecutively away from 
the apex, are longitudinally striated, and appear to be crossed 
by transverse striae. The general shape of the specimen and the 
lack of reflex curve in the plications so characteristic of Conularia, 
make it appear uncertain whether after all it belongs in this 
genus. 
Eusarcus logani 1 sp. nov. 
Plate III, figures 2-6; Plate IV, figures 1,2; Plate V, figures 1-5. 
The above species is described from the following fragments : 
post-abdominal segments ; telsons ; spines from the ectognathites 
or walking legs; manducatory edges of the gnat ho bases of the 
swimming legs; and a metastoma. 
The post-abdominal segments appear to be 5 in number 
and measure together, in the best preserved specimen, 3 cm. 
in length. At the attachment with the abdomen (the posterior 
segment of which is slightly indicated) the width is 1*8 cm. 
The terminal post-abdominal segment measures 1 ■ 1 cm. in width 
and has two lateral, posteriorly directed processes between 
which the telson was attached. The surface integument is 
covered with fine pits. 
The telsons are ensiform, straight, and from 5*5 to 8 cm. 
long, with a proximal width of 8-11 mm. They are crushed 
1 Named in honour of Sir Wm. Logan who described the beds in which the fossils were found. 
Geol. Surv. of Canada, 1863, p. 337, 
