226 MARINE BIOLOGY OF THE SUDANESE RED SEA. 
four small setze, of which the innermost is the longest. In the maxillipeds 
the large second joints are united by two pairs of coupling spines. 
The first gnathopods were present only in the larger male specimen. 
Their most characteristic feature is the large fifth joint, of which the 
homology has been considered above. It is nearly twice as long as broad, 
with the hind margin produced into a triangular tooth ; near to the hinge of 
the following joint a second, somewhat similar, tooth projects still further. 
Over this bidentate palm and considerably overlapping it the narrow so-called 
hand extends finger-like, rather abruptly crooked at the base and then gently 
convex on the outer and a little sinuous on the inner margin, the latter more 
closely setulose than the former ; from the outer end of the shortly truncate 
apex projects a minute blunt finger or nail, tipped with setules. 
The remaining limbs, with slight variations of length, are all nearly alike, 
having a rather long slender sixth joint, followed by a short finger, with a 
curved nail at apex of the inner margin and a smaller, movable, curved 
spine at the apex of the outer margin. Hansen (loc. ect. p. 304) regards the 
outer spine as the nail. 
The first pleopods of the male differ a little from those which have been 
figured for other species, the apices being simple instead of bilobed. The 
second pair differ from those figured by Sars in having the large outer part 
more squared below: whether the little part described by Hansen as exopod 
was one- or two-jointed could not be discerned ; the masculine appendix or 
endopod is acutely produced. The respiratory endopod of the third pair 
probably carries three plumose sete on the lower margin, as observed on a 
detached ramus, though absent from those figured. 
Length of larger male 2°25 mm., of the smaller 1:75 mm. 
Localities. The males taken “ 25/3/05. Crustacea &c. amg. M/. vulg. shells,” 
along with Leptochelia minuta. 
The female specimen, about the same size as the larger male, labelled 
“(4/5.11, Mise. 30.’ 
The specitic name is given in compliment to Mr. Crossland, by whom this 
and many other interesting species were obtained. 
Isopoda terrestria. 
Tribe OwrscrpeEa. 
Family TyLip &. 
1840. “ Tylosiens,” Milne-Edwards, Hist. Nat. Crustacés, vol. iii. p. 186. 
1855. Tyline, Dana, U.S. Expl. Exp. vol. xiii. pp. 715, 717. 
1877. Tylosine, Miers, Proc. Zool. Soc. London, p. 674. 
1885. Tylides, Budde-Lund, Isopoda terrestria, p. 272. 
1893. Tylide, Stebbing, Nist. Crustacea, Internat. Sci. Ser. vol. Ixxiv. p. 423. 
