120 
lying in the grooves which separate these regions. The pos- 
terior margin is more or less pointed medianly, in some ex- 
amples broad, thick, and polished, in others almost or quite 
spiniform. 
The supra-ocular border is anteriorly thrown into a pro- 
minent acute spine ; posteriorly there is a smaller one. The 
intermediate spine is well developed, projecting nearly hori- 
zontally, and further than the preceding one : it is situated 
slightly nearer this than to the post-ocular. The post-ocular 
sine is long, and is inclined in a forward direction. The he- 
patic region has a spine about the same size. The three 
lateral spines of the branchial region successively shorten. 
The sub-hepatic tubercle is papilliform, as also is that of 
the pterygostomial region. 
The basal antennal joint has r. broad, oblique sulcation, 
extending from near the external distal angle. The external 
distal spine is rather small, and is only slightly pressed up- 
ward. The remainder of the peduncle is not covered by the 
rostral horn. 
The normal chelipeds have the fingers rather long, ap- 
proximating nearly their whole length, slightly curved, and 
minutely dentate. 
The segments of the pleon in the male are moderately 
prominent in the median line. 
Length of medium-sized specimen, 45 mm. 
Breadth in the mid-branchial region, 33 mm. 
Length of rostral horn, 7 mm. 
Inter-ocular space, 11 mm. 
Length of cheliped, male, 40 mm. 
Length of first ambulatory leg, 54 mm. 
Halimus truncatipes, Miers. Plate xxii., figs. 2, 2a. 
(An. and Mag. Nat. Hist., Ser. v., vol. iv., p. 3.) 
My specimens agree well with Miers' description. The 
species attains to as large a size as 11. Urrix. The chelipeds of 
the male also are capable of assuming the larger development. 
The lateral spines are stronger, and the tubercles of the cara- 
pace more spiniform, also tubercles are shown where in the 
former species there are merely groups of bristles, the cara- 
pace itself is more convex, the rostral horns longer and a 
little depressed and more divergent. The inter-ocular tu- 
bercles are very distinct ; there are four papilliform tubercles 
occupying the front of the gastric region, the two outermost 
smaller, and not in the same transverse line. The supra- 
ocular arcuate margin has the anterior spine very prominent 
but obtuse, the intermediate spine is large, an.d has a more 
forward direction than in Tl . Icevii^. Its position with regard 
