tooth at their base. The ridge on the middle of the upper surface is little prominent, smooth 

 and does not seem to be formed by acute teeth, covering one another like tiles, as in Siv//. 

 Marte7isii\ the upper surface which is covered with a short tomentum, carries no trace of 

 the ridge and granules that are observed in Scyll. Martciisii. The inner border of the 

 5''i joint ends in an acute tooth. The terminal joint or flagellum resembles that of 5^)'//. J/ar/^f/m/; 

 the anterior margin is cut into five lobes or teeth, besides two small ones on the inner margin, 

 the posterior of which is rudimentary and which have the same form as in that species. 



The sternum (PI. II, fig. \2a) is less concave and less broad than that of Scy//. 

 Mariensii (PI. Ill, fig. 13). In the larger female of Scyll. .]faj'te)isii from Stat. 313, which has 

 the same size as the female of Scvll. bicitspidafus, the sternum, measured in the middle line, 

 appears to be 6 mm. long and 5 mm. broad between the co.vae of the 5''' pair of legs : in the 

 female of Scyll. biciispidatus it is 5'Yi mm. long and 4'/, nim. broad. The slightly concave, 

 anterior border of the first sternal somite presents a small notch in the middle line and one 

 on each side of it, so that one observes on each side a rounded prominence. The 1^' sternal 

 somite is not hollowed out as in Scyll. Martensii, but llattened; it is, however, grooved in 

 the middle and this furrow widens anteriorly. The lateral sides of the sternum are steeper 

 in Scyll. Mariensii and their surface is more uneven than in Scyll. bicuspidahis \ in the 

 latter onl\- the 5''' sternal joint carries a tubercle in the middle, the sternum is smooth, though 

 distinctly punctate on the sides, but there arc no squamiform prominences. 



The i^' pair of thoracic legs arc of a stouter shape than those oi Scyll. Martejisii, 

 their joints being broader in proportion to their length; the mcrus, for instance, is 2,3 mm. 

 long and 1,7 mm. broad pro.ximally, in ihc larger female o{ Scyll. Martciisii from Stat. 313 the 

 merus is just as long, but 1,55 mm. broad. Likewise the following legs are less slender than 

 those of Scyll. Martcusii. The [jrojjodi of the 2"'' pair (PI. II, fig. 12AJ, that are subcylindrical, 

 though tapering towards the distal end, are 2,4 mm. long, measured in the middle of their outer 

 surface, 0,76 mm. broad at the pro.ximal end of their upper margin and 0,52 mm. at the distal 

 extremity; the terminal joints are 1,9 mm. IcMig and 0,42 mm. thick at their base. In the 

 larger female of Scyll. Mariensii from Stat. 313 the propodus of the 2°'' legs is 2,3 mm. long, 

 0,74 mm. broad at the ]iroximal and 0,52 mm. at the distal end; the dactylus is 2,65 mm. long 

 and 0,42 mm. thick at its base. While the propodi of these legs have the same form in both 

 species, the merus, the carpus and especially the dactylus appear distinctly stouter, less 

 slender than in Scyll. Martciisii\ the dactxlus e.g. is shorter than the propodus, instead of 

 longer, and it appears less .slender. The propodi of the i"^ legs (PI. II, fig. \2c) are 2,3 mm. long, 

 o,7cS mm. broad a little beyond their proximal extremity and 0,54 nun. at their distal extremity; 

 the dactylus is 1,45 nun. long and i),42 mm. l)road at base. In the larger female oi Scyll. 

 Mariensii from Stat. 313 the propodi of these legs are 2,3 mm. long, 0,7 mm. broad a little 

 beyond their proximal extremity and 0,48 mm. at the distal one; the dactylus is 2,1 mm. long 

 and 0,38 mm. thick at its base. In Scyll. biciispidatiis these i)ropodi are 3'/.,-times as long as 

 their average width and one and a half as long as the terminal joints, in Scyll. Mariensii 

 4-times as long as their average width and little longer than their dactyli. The propodi of the 

 3'''^ legs are distinctl)' somewhat compressed: they present on their outer surface two 



