1895. | NEW YORK ACADEMY OF SCIENCES. 145 
conical or cylindro-conical, prominent, marked by furrows on the 
sides, and distinct from the occipital ring. Fixed cheeks of 
variable width, bordered by a long, continuous or nearly con- 
tinuous eyelobe. Extension of the dorsal suture both in front 
of and behind the eye, more or less clirect to the margin. 
Movable cheek regularly curved, area wider than the distinct 
fold, spine usually long. 
Thorax of many joints, pleure grooved for part of their length, 
more or less geniculate, curved backward in the distal part, ex- 
tended into points or spines. 
Pygidium in the Canadian species unknown (small?) in the 
Sardinian species like that of Olenus or Paradoxides. 
PROTOLENUS PARADOXOIDES PI. x., figs. 3 a and bd. 
Nat. Hist. Soc. N. Bruns’k, Bull. 10, p. 36, fig. 2. 
Trans. Roy. Soc. Can., vol. xi., p. 101, pl. xvii., fig. 10 a@ and b. 
The thorax in this species is narrow, owing to the shortness of 
the pleurz ; the ring is prominent and has a strong furrow, and 
the pleura is flat and carries a diagonal groove, which terminates 
at the root of the spine; the spine is short and bent abruptly 
backward. 
Part of a hypostome has been preserved; it is dome-like in 
form, and the interior has numerous arched thread-like furrows. 
PROTOLENUS BI-TUBERCULATUS n. sp. PI. x., figs. 4 a to c. 
Only the middle piece of the head shield is known. The front 
margin is broken. leaving only the area, which is narrow. Gla- 
bella cylindro-conical, moderately raised, enclosed by a distinct 
dorsal furrow, which is but faintly impressed at the front; the 
glabella has three pairs of oblique furrows, the two posterior 
sharply impressed, and connected over the axis by a shallow de- 
pression ; the posterior lobe of the glabella bears a pair of small 
oval tubercles near the front, and about midway of each half. 
The occipital ring is only partly preserved, and is separated from 
the glabella by a sharp furrow, directly transverse. The fixed 
cheek is flat and somewhat concave along the middle; it has a 
small, low, longitudinal ridge near the posterior inner corner, and 
a tubercle-like ocular fillet; the eyelobe is mostly broken away, 
but the form of the cheek indicates that it was continuous. 
The thorax is narrow. A portion of one, supposed to be of 
this species, found in the lower layer of Assise 3, shows a strong 
grooved ring, having a pair of tubercles in the groove; the 
pleure are partly preserved. 
Horizon and locality. The head-shield is from the upper part 
of Assise 3 at Hanford Brook. 
TRANSACTIONS N. Y. ACAD. Sc¥., Vol. XIV., Sig. 10, May 18, 1895. 
