DECAPOD CRUSTACEA FROM ItfADAGASCAR. 921 



Epigastric crests not very pi'ominent, more or less rugose, 

 hardly oblique, situated entirely behind a line joining epi- 

 brancliial teeth ; they are continued, without interruption, into 

 the protogastric portions of postorbital crest, which are very low, 

 rounded, and ill-defined, except in so far as they are limited 

 by the transverse depression behind each orbit ; in general 

 direction the postorbital crest is transverse, and it is not trace- 

 able external to its intersection by the cervical groove. Groove 

 between the epigastric lobes bifui'cating widely behind, the limbs 

 angularly bent so as to become parallel. Front strongly deflexed, 

 but with anterior margin visible from above ; divided into two 

 low rounded lobes, most distinct from above, less so from in 

 front ; with a smooth raised marginal line. Upper margin of 

 orbit with a prominent smooth border, inclined forwards, with 

 only a faint trace of a lobe in the middle, towards the exorbital 

 angle which is not at all prominent or dentiform. Lower margin 

 of orbit nearly straight as seen from below, and smooth or 

 obscurely crenulated ; without any trace of a notch or sinus 

 below the exorbital angle. Antero-lateral margin stiongly arched, 

 with a distinct marginal line, which is smooth or, in the smallest 

 specimen, obscurely crenulate, and runs on to dorsal surface 

 behind. Postero-lateral border concave, withmoi-e or less distinct 

 lines. Ptei-ygostomial region and, less conspicuously, subhepatic 

 region beset with tubercles. 



Merus of third maxillipeds slightly wider than long ; ischial 

 groove rather nearer the inner than the outer margin. 



Chelipeds unequal. Lower surface of merus margined with 

 tubei'cles, which may become indistinct ; a small blunt tooth near 

 distal end of inner edge; upper edge rugose with a low subr 

 terminal tubercle. Carpus smooth and punctate externally ; 

 with two teeth on inner side and a variable number of small 

 granules. Surface of hand smooth and rather coarsely punctate ; 

 fingers long, slender, and strongly deflexed. 



Sixth somite of male abdomen shoi'ter than its distal Avidth. 



Holotype, male, 33 mm. in length, in British Museum. Para- 

 types, the two other males mentioned above, in Pretoria Museum. 



Remarks. — This species resembles, on the one hand, P. goudoti 

 and, on the other, the smooth form of P. madagascariense described 

 under Series D above. From the former it differs chiefly in the 

 wider carapace (the concavity of the postero-lateral borders has 

 the eflfect of increasing the apparent difference in this respect) ; 

 in having the epigastric crests neai-ly transverse, lying behind 

 instead of in front of the line joining the epibranchial teeth, and 

 quite continuous with the obsolescent postorbital crests ; in having 

 the gastric region less elevated and the transvei-se convexity of the 

 carapace therefore less mai'ked ; and in having no notch below 

 the external orbital angle. Compared with P. madagascarievse 

 the sa,me difterences hold good, even although in that species the 

 epigastric crests are less oblique and less advanced than they are 

 in P. goudoti. 



