REPORT ON THE BRACHYURA. 
185 
legs present nothing remarkable ; the merus-joint of the fifth (natatory) legs is not armed 
with a spine on its inferior margin . 1 
The only recent species of this genus is the very common and widely distributed 
Indo-Pacific species which follows : — 
Scylla serrata (Forskal). 
Cancer serratus , Forskal, Descript, animalium quae in itinere orientali observavit P. Eorskal, 
p. 90, 1775. 
Portunus ( Scylla ) serratus, de Haan, Crust, in v. Siebold, Fauna Japonica, p. 44, 1835. 
Scylla serrata, A. Milne Edwards, Ann. d. Sci. Nat., ser. 4, Zool., xiv. p. 252, pis. i., ii., 1860 ; 
Archiv. Mus. Hist. Nat., vol. x. p. 349, 1861, et synonyma. 
Tahiti, Papiete. An adult female and a smaller male. 
(J . Lines. Millims. 
Length of carapace, about ...... 27 57'5 
Breadth of carapace, nearly ...... 37-|- 79 
Lupocyclus , Adams and White. 
Lupocyclus, Adams and White, Crust, in Zool. H.M.S. “Samarang,” p. 47, pi. xii. fig. 4, 1848. 
„ A. Milne Edwards, Archiv. Mus. Hist. Nat., vol. x. p. 387, 1861. 
Carapace transverse, but little broader than long ; the antero-lateral margins armed 
with five regular and even teeth, between which may alternate several smaller teeth ; 
the last antero-lateral tooth may be (subgenus Paratliranites ) elongated and laterally 
porrected ; the front is narrow, moderately prominent, and four to six-lobecl. The 
orbital fissures are very distinct. The longitudinal ridges of the endostome or palate 
are distinctly defined ; the post-abdomen may have, as in so many Portunidse, two or 
three of the intermediate segments coalescent. The eyes are set on very short pedicels. 
The basal antennal joint is free, neither united with the front nor with the interior wall 
of the orbit, it is narrow or moderately dilated, not produced at the antero- external 
angle, and lies within the interior orbital hiatus. The ischium of the exterior maxilli- 
pedes is not produced at its antero-internal angle ; the merus is somewhat elongated, 
and rounded or subtruncated at the distal extremity, but little, if at all, emarginated at 
the antero-internal angle. The chelipedes are subequal and moderately slender, the 
joints are armed with spines, and the palms are externally costated. The ambulatory 
legs of the second, third, and fourth pairs are slender, and the dactyli are styliform ; in 
the fifth legs the penultimate and terminal joints are dilated, and the terminal joints 
ovate, as in other Portunidse. 
1 In this 'genus the longitudinal ridges of the epistoma are sometimes partially or obscurely developed. The 
epistoma is transversely sulcated, but this sulcus, upon which much stress is laid by A. Milne Edwards as a generic 
character, is not always very distinct. 
(zool. chall. exp. — part xlix. — 1886.) 
Ccc 24 
