82 
THE VOYAGE OF H.M.S. CHALLENGER. 
pubescence and with some longer curled hairs. Colour (in spirit) yellowish-brown ; tips 
of the fingers of the chelipedes, black. 
The largest male presents the following dimensions : — 
Adult (J . 
Length of carapace, nearly 
Length of rostrum, about 
Breadth of carapace, about 
Length of a chelipede, about . 
Length of first ambulatory leg, 
I.ines. Millims. 
13 27 
H 5 
11 23 
18 1- 39 
Id" 30 
Bahia, shallow water (an adult female), Fernandho Noronha, 7 to 20 fathoms. An 
adult, smaller and young male, and two small females. 
The nearest ally to this species is the Macrocoeloma eutheca (Stimpson), 1 which 
Macrocceloma concava resembles in the great development of the orbits, but in Macro- 
coeloma concava the carapace at the branchial regions is much broader, the spines and 
tubercles of its dorsal surface more numerous, and the lateral epibranchial spine is 
longer. The spines of the rostrum are described by Stimpson as parallel in Pericera 
eutheca. I have observed no specimens in the Challenger series resembling Pericera 
eutheca in the characters mentioned, but it is possible a larger series would show the 
two species to be identical. 
Microphrys, Milne Edwards. 
Microphrys, Milne Edwards, Ann. d. Sci. Nat. Zool., ser. 3, vol. xvi. p. 251, 1851. 
„ A. Milne Edwards, Crust, in Miss. Sci. au Mexique, p. 59, 1875. 
„ Miers, Journ. Linn. Soc. Lond. (Zool.), vol. xiv. p. 664, 1879, and synonyma. 
Carapace broadly subpyriform, and somewhat depressed, with the dorsal surface 
uneven and tuberculated, with a small lateral epibranchial spine ; prteocular spine 
sometimes not developed. Orbits small, circular, with closed fissures. Spines of rostrum 
slender and more or less divergent. Post-abdomen, in the male, distinctly seven- 
jointed (in the species examined). Eyes small. Basal antennal joint considerably 
dilated and armed with a long spine at the antero- external angle which is visible in a 
dorsal view; the mobile joints and the flagella are not concealed by the rostral spines. 
The merus of the exterior maxillipedes is distally truncated, with the antero-external 
angle somewhat produced and rounded, and the antero-internal angle emarginate. The 
chelipedes are moderately developed, with the palm compressed and more or less 
enlarged ; fingers with a wide intermarginal hiatus. The ambulatory legs are rather 
short, with the merus and carpus joints sometimes armed with spines ; the dactyli 
slightly curved. 
1 Pericera eutheca, Stimpson, Bull. Mus. Comp. Zool., vol. ii. p. 112, 1870 ; A. Milne Edwards, Crust, in Miss. Sci. 
au Mexique, pt. 5, p. 58, pi. xvcc. fig. 1, 1873. 
