32 
MUSEUM BULLETIN No. 31 
2 *5 mm. thick at the base. The free -cheek is 22 mm. long, from back 
of neek-ring to front across eye, and the spine extends 25 mm. back 
of nuchal segment. From inner posterior angle of eye to outer 
margin, on a line perpendicular to the axis of the trilobite, the cheek 
is 15 mm. wide. 
With the additional knowledge afforded by these specimens it 
may still be said that Bathyurus ingalli is closely related to B. 
spinigerj but differs from that species in its larger size, much larger 
spine on the neck ring, wider border on cranidium and free cheeks, 
wider and less pustulose free cheeks, wider pygidium, and a more 
posterior position of the spine on that shield. 
Horizon and Locality . Common in the u crinoid beds ” at the 
liftlock at Kirkfield, and rare at the same horizon near Bellevue and 
Ottawa. Specimens collected by W. A. Johnston, E. J. Whittaker, 
and the writer. 
Genus, Goldius de Koninck. 
Ooldius lunatus (Billings). 
Plate IX, figure 8. 
Bronteus lunatus Billings. Geol. Surv., Can., Rept. of Prog., for 
1853-56, 1857, p. 338. Geology of Canada, 1863, p. 188, fig. 
187. For further references see Bassler, Bull. 92, TT.S. Nat. 
Mus., 1915, p. 559. 
Thi8 still remains a rare fossil, but Billings’ figure is so often 
reproduced that it has been deemed advisable to include a photograph 
of one of the cotypes, which is not so well preserved as would be sug- 
gested by the illustration in the <£ Geology of Canada, 1863.” Enough 
specimens are known, however, to justify the restoration. 
The type is from the upper part of the middle Trenton along the 
Ottawa river, at Ottawa. 
Genus, Hemiarges Giirich. 
Hemiarges paulianus (Clarke). 
Plate IX, figure 2. 
Arges wesenbergensis var. paulianus Olarke, Pal. Minn., 3, PI. 2, 
1894, p. 744, figs. 62-64. 
This is a small and rare trilobite, which has not been well figured. 
The illustration is of a fairly well-preserved cranidium collected by 
Mr. Whittaker near the liftlock at Kirkfield. 
Description. Cranidium small, broader than long, the surface 
eovered with relatively large pustules. Glabella divided into five lobes. 
