9 2 



rounded lobes or teeth and two smaller ones, also rat her obtuse, are 

 moreover observed on its inner margin; the i st lobe is a little broader than the 

 three following, that are nearly equal, the 5 th is a little less broad and the two teeth on the 

 inner margin are smaller and narrower. The 4 th lobe reaches farthest forward. In Scyll. sordidus 

 the anterior margin presents only four rounded lobes, besides two on the inner margin, so that 

 Scyll. gibberosus has one lobe more. 



The sternum (Fig. 14a), measured in the middle line, appears to be 4 1 /., mm. long; it 

 is 3 3 / 4 mm. broad between the coxae of the 5* legs, the proportion between both measurements 

 being the same as in Scyll. sordidus. The sternum, however, is a little more concave; the 

 i st joint is emarginate anteriorly, but the emargination is not triangular, acute, but 

 semicircular and immediately behind it, the i st joint presents a triangular concavity, that 

 narrows backward. The sternum is smooth, but the 5 th joint carries a rounded tubercle in 

 the middle line. 



The thoracic legs resemble closely those of Scyll. sordidus, the differences are, 110 

 doubt, very slight. The subcylindrical, tapering propodi of the 2 nd legs (Fig. 14.C) are a little 

 slenderer, the compressed propodi of the 3 rd pair (Fig. 14*/) appear, on the contrary, slightly 

 broader and they are faintly grooved near the lower border of their outer surface. The similarity 

 between both species is even so large, that the joints of the four posterior pairs are marked 

 with the same, slate-coloured, dark rings as those of Scyll. sordidus. 



The abdominal appendages are not yet fully developed. While those of the i st pair 

 are wanting, the pleopods of the 2 nd are biramous, the two rami slender, narrow, of unequal 

 len^th, the longer almost twice as long, but a little less broad than the other; except two 

 short, plumose setae near the extremity of the longer ramus, these appendages are glabrous. 

 The pleopods of the 3 vd — 5* somites are very small, biramous, the rami slender, narrow, 

 glabrous, nearly equally broad along their whole length, obtuse, one a little longer than the 

 other: those of the 3 rd somite are 0,56 mm. long, the longer branch 0,12 mm. longer than 

 the other. 



This specimen is grayish coloured with a pale reddish tinge on the abdomen. 



The young male from North-Ubian is somewhat younger and fully agrees with the 

 preceding description. 



Scyll. gibberosus chiefiy differs from Scyll. arctus (L.) by the following characters. The 

 three teeth in the middle line of the carapace before the cervical groove are in Scyll. arctus 

 all quite sharp, especially the middle one. The squamiform prominences are a little smaller 

 and those of the lateral carinae are not carinate. The antero-lateral angles are sharper and 

 more prominent. The sculptured part of the 4 th abdominal tergum, though not shorter than 

 that of the 3 rd , is not at all prominent, not higher than the latter. The proximal (outer) squame 

 is distinctly longer than broad and its distal end is sharper. The emargination of the anterior 

 extremity of the sternum has another form. The propodi and dactyli of the 2 nd legs are 

 less slender. 



