60 
VICTORIA MEMORIAL MUSEUM. BULLETIN NO. 
Family Solenopleurida?, Angelin. 
Genus Hystricurus nov. 
(hystrix, porcupine; oura, tail.) 
Bathyurus conicus and B. cordai differ from typical Bathyurus 
in the glabella, which is short and tapers towards the front, 
instead of expanding in that direction. The elevated ridge on 
the fixed cheeks outside the dorsal furrow is another feature 
unknown in Bathyurus , but reminds one of Ptychaspis or Cy- 
phaspis . The affinities of the genus seem to be with Solenopleura 
and Ptychoparia , the general shape of the glabella, the course 
of the sutures, the form of the cranidium in front of the glabella, 
and the pygidium, are similar in these genera. Hystricurus 
differs from Ptychoparia in having the glabella somewhat longer 
and unfurrowed, and in the absence of eye lines. Unfortuna- 
tely, the thorax of the present genus is unknown. 
Generic Diagnosis. 
Glabella conical, tapering towards the front, outlined by deep 
furrows at sides and front. Glabellar furrows absent. Fixed 
cheeks long, extending nearly to the genal angles. Dorsal fur- 
rows paralleled by a narrow convex ridge. Eyes of medium 
size, situated opposite the middle of the glabella. Cranidium 
with deeply concave border in front. 
Pygidium rounded, with concave border. Axial lobe prom- 
inent, with 5 rings, and there are five pairs of ribs on the pleural 
lobes. Surface smooth or pustulose. 
Type, Bathyurus conicus , Billings. 
Hystricurus conicus, (Billings). 
Plate VII, fig. 9. 
Bathyurus conicus f Billings, 1859. Canadian Naturalist and 
Geologist, Vol. IV, p. 366, fig. 12c. 
Thesurfaceisstronglypustulose. Itisfound intheBeekmantown 
at St. Timothy and elsewhere on the Beauharnois canal in 
Quebec, at Fort Casein, Vt., and at Fort Ticonderoga and 
Comstock Landing, New York. 
