BY R. ETHERIDGE, JUNR., AND JOHN MITCHELL. 489 
Phacops Crossleii, sp.nov. 
(PI. xxxix., figs. 9-11.) 
Sp. Char. — Body — oblong-oval. Head-shield or cephalon — Semi- 
circular, rather flattened above, sides abruptly depressed; glabella 
large, subpentagonal, greatly contracted behind, highest between 
the eyes, very slightly arched in front, overhanging the front 
border, rounded so that taking for centre the middle point of the 
confluent basal pair of glabella furrows, the curve forms the arc 
of a circle with radius equal to the length between the point 
mentioned and its front, tolerably inflated, sides straight, inclined 
inwards at an angle of 60°, greatest width equal to length 
including neck ring, coarsely granulate; intercalary furrows dis- 
tinct, deep (in casts) at sides and close to the neck furrow, with 
which they communicate, thus forming prominent basal lobes; 
second pair linear, feeble and falcate, and seem, in some speci- 
mens, to communicate with the basal pair, and with the axial 
grooves; first or frontal pair linear, faint and feeble, arising from 
the axial furrow at the front corners of the glabella, and 
traversing it in a very widely Y-shaped manner, the inner portion 
being shortest and slightly falcate; frontal lobes very large, 
second pair cleaver-shaped, third pair suboblong, fourth pair 
nodular; neck furrow very distinct, continued across the side 
lobes with equal distinctness; and faintly along the inner edge of 
the border of the free cheeks to the front of the axial groove; 
neck ring robust, strongly arched, granulate, one large granule in 
the middle line; axial grooves A^ery distinct, deep and wide; fixed 
cheeks small; genal lobes* moderately arched, granulate and 
separated from the palpebral lobes by distinct shallow furrows, 
which pass posteriorly round and under the eyes, giving relief to 
those organs. Eyes large, equal in length to half of the longi- 
tudinal length of the cheek, anteriorly scarcely reach the front 
* That portion of the fixed cheek between the palpehral lobe and axial 
furrow and bounded posteriorly by the lateral extension of the neck furrow. 
