REPORT ON THE BRACHYURA. 
143 
Pseudozius bouvieri, var. mellissii (PI. XII. fig. 3). 
% Xantho bouvieri, A. Milne Edwards, Rev. and Mag. Zool., vol. xxi. p. 377, 1869. 
Pseudozius mellissii , Miers, Ann. and Mag. Nat. Hist., ser. 5, vol. viii. p. 432, 1881. 
Ascension Island (an adult female). 
This specimen was received among the fishes of the Challenger collection. 
Carapace naked, transverse, much broader than long, its surface punctulated, the 
punctulations numerous and crowded in front, sparser posteriorly, and nearly obsolete 
near the postero-lateral and posterior margins. Some larger pits occur here and there 
near the antero-lateral margins, and the upper margins of the carpus and hand of the 
chelipedes are also punctulated. The front is four-lobed ; the two median lobes are 
prominent and rounded, and separated by a median notch ; the outer lobes (or inner 
orbital angles) are very little prominent, and separated from the median lobes only by a 
rather shallow sinus. The antero-lateral margins are longer than the postero-lateral 
margins, and are defined along the greater part of their length by a low, obliquely-striated, 
entire line or crest ; after which follow, at the broadest part of the carapace, two small 
but distinctly defined teeth. All the segments of the post-abdomen are distinct in both 
sexes ; the two basal segments cover the whole width of the sternal surface between the 
bases of the fifth ambulatory legs. The chelipedes are large and robust ; the arm or merus- 
joint short, trigonous, with the margins unarmed ; carpus large, with its inner margin 
produced into a broad, squarely truncated lobe ; the palm has its upper margin rounded, 
the lower margin straight, thin-edged and entire ; inner surface with a rounded 
prominence ; fingers black, dentated on their inner margins, with acute apices, the 
coloration not extending over the inner or outer surface of the palm. Ambulatory legs 
slender, smooth, and nearly naked, with the penultimate and terminal joints canaliculated, 
the longitudinal channels on the penultimate joints not always extending along the 
whole length of the joints ; the legs of the fourth pair are longer than those of the 
third pair. The colour in spirit is reddish or bluish-pink. 
Adult $ . Lines. Millims. 
Lengtli of carapace, about . . . . . . 12 25 
Breadth of carapace, . . . . . . . 18 38 
In a larger male from St. Helena, in the collection of the British Museum, the 
carapace is even more transverse. 
It is with much hesitation that this form is identified with Xantlio bouvieri, A. Milne 
Edwards, which is very briefly described, and has not, I believe, been figured, nor am I 
certain from the short description whether Xantho bouvieri be properly a Pseudozius, 
since it is not stated whether the ridges of the endostome are at all developed. 
The specimens from St. Helena and Ascension Island differ in the distinctly four- 
lobed front from A. Milne Edwards’ description. 
