70 
T. V. HODGSON. 
Notopais spicatus. 
(Plate VIII., fig. 1.) 
Specific characters :— 
Cephalosome armed dorsally, with two stout spines and two lateral ones. 
Mesosome with the five anterior segments armed with four strong forwardly directed spines, the 
first four segments having others laterally. 
Urosome triangular, truncated, with minute terminal uropoda. 
The cephalosome is wide, nearly as wide as any other part of the body. Its 
anterior margin appears to be rounded, but close examination shows that it is deeply 
excavated, and the first pair of antennas arise near the anterior border of this 
excavation. Not far from the rounded lateral margins of the cephalon is a small but 
distinct spine, and there are two more prominent dorsally, but more distant from the 
middle line than on succeeding segments. 
The impression one receives in examining this animal is that the cephalon and 
first segment of the thorax are distinct, the latter being much smaller than, and above 
the former, a condition which occurs in the genera Ilycirachna and Pseudarachna of 
Prof. G. 0. Sars. 
Of the mesosome the first two segments are subequal, and the tw T o following ones 
are also subequal but a little longer, their anterior margins are provided wfith four 
stout and prominent spines directed forwards, these are placed at approximately equal 
distances apart, the median pair being the largest. The epimera are rather elongated, 
not separable from the body, but where they might be^said to arise is a small, blunt 
spine ; the epimeron itself is in each case rounded, and about the middle of its margin 
is another spine not so large as the dorsal ones ; an additional one arises at their 
anterior margins in the first, second, and fourth of these segments. The three posterior 
segments are separated from the preceding by a distinct waist. These segments are 
curved backwards ; the first tw T o are subequal, the third is about half the size ; the 
anterior margin of the first bears four large spines similar to those on the preceding 
segments. 
The metasome comprises a single plate, the urosome, which is a truncated triangle, 
its margins sloping from the mid-dorsal line. It is covered with fine setm more thickly 
than the rest of the body, where they are rather sparingly distributed. The uropoda are 
minute, terminal, and arise ventrally. Each consists of a very small exopodite, a rather 
barrel-shaped and diminutive endopodite of about half the size, both terminating in a 
few setae. 
The first antennae arise quite close to the middle line just below the upper margin 
of the cephalon ; the first joint of the peduncle is very large comparatively and bears 
tw T o teeth on its inner distal margin ; it terminates as a cone, and on the upper surface 
of this are one or two short joints, I cannot be certain which it is ; the flagellum is very 
slender and consists of a long joint, a very short joint and a long portion in w r hich the 
articulations under existing conditions are indistinguishable. 
O O 
