16 SLADEN TRUST EXPEDITIONS TO ABliOLHOS ISLANDS. 
is covered with larger and smaller tubercles. The posterior part o£ the abdo- 
men has, in the main, three large bosses — an anterior pair, one on each side 
of the middle line, and behind them a single median posterior boss. The 
anterior pair of: bosses are somewhat elliptical in shape, and each bears a 
large, prominent, almost erect, conical spine with additional spines at its 
apex. Behind this prominent spine are four or five sharply-pointed tubercles, 
more prominent than the rest of the tubercles and gi-anulations covering the 
surface. The posterior median boss is circular in outline, quite smooth and 
polished, and bearing a single almost erect stout conical spine. The posterior 
margin of the abdomen is tridentate; the median lobe rather longer than the 
lateral lobes, with the apex truncate and bearing two spine-like tubercles. 
The lateral lobes have their apex pointed and bearing a single spine-like 
tubercle. The uropods extend some way behind the posterior margin of the 
abdomen ; their dosal surface is covered with fine granulations, with here and 
there a larger and more prominent tubercle. The inner branch is longer and 
stouter than the outer ; its apex obtusely rounded, with a spine-like tubercle 
at its tip. The outer branch is more pointed than the inner, and has a similar 
spiniform tubercle at the apex. The mouth-parts and thoracic appendages 
present no special features, and the figures which I give of the peduncles of 
the antennules and attennte, second and eighth thoracic limbs will serve to 
show the general structure of these appendages. The second to the eighth 
thoracic limbs are stout and bi-unguiculate, with an armature of strong- 
spines on the inner margin of the merus, carpus, and propodus. 
The pleopods are typically hemibranchiate, with ihe exopods of the third, 
fourth, and fifth pairs two-jointed. The appendix masculina on the second 
pair of the male is nearly twice as long as the branches, narrowing to a 
finely-pointed apex, the distal portion curved slightly inwards. 
The female differs from the male in having the body smooth, without 
tubercles and granules, and with the hairs on the thorax and abdomen very 
short and very much less numerous. The anterior part of the abdomen^ 
i.e. the combined first four segments, has the general surface raised inta 
two obscure bosses. The terminal portion of the abdomen has likewise two 
bosses, more clearly defined and separated medianly by a shallow groove.. 
The posterior margin is tridentate ; the median lobe somewhat larger than 
the lateral lobes, with its apex bluntly rounded. 
Among all the described species of the genus Cijmodoce, this species comes 
nearest to C. pilosa, M. Ed., and its allies C. longisti/Us, Miers, C. bicarhiata,, 
Stebbing, and C. Zanzibar ensis, JStebbing, but differs from all of these species 
by the large, conical, erect spine which crow ns each of the three main bosses 
of the abdomen. I have associated the name of the discoverer of the 
Abrolhos group of islands with this pretty little species found there by 
Professor Dakin. 
