REPORT ON THE BRACHYURA. 
235 
It is unfortunately in very imperfect condition, having lost the right chelipede and 
several of the ambulatory legs, which are rather more slender than in the description of 
Dr. Stimpson, and the front is subentire, not distinctly notched. 
Ceratoplax arcuata, Miers. 
Ceratoplax arcuata , Miers, Crust, in Rep. Zool. Coll. H.M.S. “ Alert,” p. 243, pi. xxv. fig. B, 
1884. 
A female specimen dredged south of New Guinea, in 28 fathoms, in lat. 9° 59' 0" S., 
long. 139° 42' 0 " E. (Station 188) is referred, but doubtfully, to this species. 
This example is of much larger size than the small male described in the Report 
cited ; the whole animal is more pubescent and the carapace proportionately broader ; the 
subdistal tooth or prominence on the upper margin of the merus of the chelipedes, which 
is very obscurely indicated in the original type, is more distinctly developed . 1 It has the 
following dimensions : — 
Adult ?. 
Lines. 
Millims. 
Length of carapace, nearly 
4 * 
9-5 
Breadth of carapace, .... 
H 
11-5 
Notonyx, A. Milne Edwards. 
Notonyx, A Milne Edwards, Nouv. Archiv. Mus. Hist. Nat., vol. ix. p. 268, 1873. 
Carapace nearly quadrilateral, with the antero-lateral angles rounded, subcristated, 
and the lateral margins straight, entire, and subparallel; longitudinally it is slightly 
convex, and the dorsal surface smooth and polished. Front deflexecl, about one-third 
the width of the carapace, with the anterior margin straight and entire. The orbits, 
antennae and post-abdomen are nearly as in Ceratoplcix. The eye-peduncles have the 
corneae normally developed. The exterior maxillipecles are nearly as in Ceratoplax, 
but the merus-joint, in the specimens I have examined, is subquadrilateral, distally trun- 
cated, and is not produced at its antero-external angle. The chelipedes are subequal and 
moderately developed ; merus trigonous ; carpus with a tubercle or prominence, not a 
spine, on its interior surface ; palm short and compressed, cristated below ; fingers distally 
acute. The ambulatory legs, as in Ceratoplax, are slender and moderately elongated, 
with the joints unarmed ; dactyli nearly straight. 
1 1 very much doubt the generic distinctness of Iihizopa gracilipes, Stimpson (from Hong- Kong), from this species. 
In specimens, probably from the Chinese Seas, referred doubtfully to Iihizopa gracilipes in the British (Natural 
History) Museum, the ocular cornea: are minute and inferior as in Ceratoplax, but the merus of the exterior maxillipedes 
is not produced at its antero-external angle; the basal antennal joint is more robust and quadrate. In the fully grown 
specimen the frontal margin is entire, and the palms of the chelipedes are cristate and externally glabrous, as in 
Stunpson’s description. 
