REPORT ON THE BRACHYURA. 
113 
Lophactsea, A. Milne Edwards. 
Lophad&a, A. Milne Edwards, Ann. d. Sci. Nat., ser. 4, Zool., vol. xviii. p. 43, 1862; Nouv. 
Archiv. Mus. Hist. Nat., vol. i. p. 245, 1865. 
Carapace transverse, convex, its dorsal surface very distinctly lobulated in its anterior 
half, and often granulated. The antero-lateral margins are longer than the concave 
postero-lateral margins, and not dentated as in Lophozozymus, but defined by a carina or 
crest, which is more or less distinctly interrupted by narrow fissures. The cervical suture 
and the depressions between the lobules of the dorsal surface are usually distinct and 
smooth. The front is deflexed, not very prominent, and is rough, usually about one- 
third the width of the carapace ; its anterior margin is sinuated and nearly straight, with 
usually a narrow median fissure. The post-abdomen in the male is usually five-jointed, with 
the third to the fifth segments coalescent. The eyes, antennae, and exterior maxillipedes 
differ in no essential particular from the same parts in Atergatis. The chelipedes (in the 
adult male) are moderately robust and subequal ; the merus-joint very short, carpus and 
palm smooth or granulated on the upper surface, palm sometimes carinated above, dactyl i 
usually carinated on the superior margins. The ambulatory legs are short, laterally 
compressed ; the fourth to the sixth joints dilated and carinated on the superior margins ; 
dactyli slender, nearly straight, and usually longer than the penultimate joints. 
This genus can only be distinguished from Atergatis by the lobulated carapace, and 
from Lophozozymus by the absence of antero-lateral marginal teeth. 
The species occur in the Indo-Pacific region, one ( Lophactsea lohata) also in the 
West Indian Seas and Gulf of Mexico, and at Bermuda; one ( Lophactsea picta) at 
the Cape Verde Islands, St. Lucia, and Salamanca, and one ( Lophactsea rotundata ) 
at Cape St. Lucas, California (cf. A. Milne Edwards, Crust, in Miss. Sci. au Mexique, 
pt. 5, pp. 242, 243, 1879, for synonyma). 
The following have been described since Milne Edwards’ Monograph was published in 
1865 :— 
Lophactsea picta , A. Milne Edwards. St. Lucia ; Salamanca. 
Lophactsea violacea, A. Milne Edwards. New Caledonia. 
Lophactsea helleri, Kossmann. Bed Sea. 
Lophactsea lohata, A. Milne Edwards. 
1 Cancer spedabilis, Herbst, Naturgesch. der Krabben u. Krebse, vol. ii. Heft. v. p. 153, 
pi. xxxvii. fig. 5, 1794. 
„ lobatus, Milne Edwards, Hist. Nat. Crust, vol. i. p. 375, 1834. 
Lopbadeea lobata, A Milne Edwards, Nouv. Archiv. Mus. Hist. Nat., vol. i. p. 249, pi. xvi. 
fig. 3, 1865 ; Crust, in Miss. Sci. au Mexique, pt. 5, p. 242, 1879, et synonyma. 
Bermuda, on the shore (an adult male and two females, whereof one bears ova). 
In no two of the specimens of this species is the pattern defined by the coloured lines 
(zool. chall. exp.— part xlix. — 1886.) Ccc 15 
