170 A. Alcock — Carcinological Fauna of India. [No. 2, 
ii. Gastric region with a sharp tubercle or 
spine ... ... ...A. spinosus. 
II. Carapace with a long post-ocular neck: dactyli of 
last pair of legs hardly curved :— 
1. Lobes of rostrum with a spinate carina: median 
tubercles of carapace low and blunt ... A. cadelli. 
2. Lobes of rostrum with a smooth carina: median 
tubercles of carapace sharp and elevated A. tenuicollis . 
Achaeus tenuicollis, Miers. 
Achseus tenuicollis , Miers ‘ Challenger * Brachyura, p. 9, PI. I. fig. 3. 
“ The body is thinly clothed with short curled hairs; the limbs 
with similar hairs, interspersed among which are some longer ones. 
The carapace is subtriangulate, little longer than broad, with a neck-like 
constriction behind the orbits, and armed with spines as follows —Three 
conical spines upon the gastric and another upon the cardiac region, two 
shorter conical spines or tubercles whereof the anterior is the smallest, 
on each branchial region, behind these one very small on the posterior 
mar gin of the carapace, and another on the sides of the branchial regions 
above the bases of the chelipedes; also a small spine upon the 
rounded, lateral, hepatic protuberance, and another behind this, on the 
pterygostomian region; there is also a strong spinule on the upper 
margin of the orbit, above the eye-peduncles. The lobes of the rostrum 
are short, and terminate each in a spine. The sternal surface of the 
body bears a few spinules. The post-abdomen of the male, is as usual, 
six-jointed (the two last joints having coalesced). The eye-peduncles 
are robust, with the cornese protuberant; a small spinule exists on the 
inferior margin of the eye-peduncle, and another on the upper margin 
of the eye, near the distal extremity. The antennules are lodged in 
deep longitudinal fossettes; the very slender basal joint of the antennae 
is joined with the front at its distal extremity and bears several small 
spinules on its inferior surface, the following joint is short, the next 
about as long as the basal joint, flagella slender; the ischium-joint of 
the outer maxillipedes is produced at its inner and distal angle which 
is rounded and bears several spinules on its outer surface, as does also 
the rnerus-joint which is rounded, not truncated, at the distal extremity 
where it bears the next joint. The chelipedes (in the male) are rather 
slender, and longer than the body; with the joints clothed with rather 
long hairs ; ischium and merus-joints with a series of spinules on their 
anfero- and postero-inferior faces, wrist about as long as palm, with a 
few spinules hardly discernible amid the hairs which clothe this joint, 
