CBT7STACEA OP THE MEEGUI AECHIPELAaO. 81 



depressed, and the two median teeth are most prominent. The 

 second teetii are directed somewhat obliquely outwards and sepa- 

 rated from the third, which extends straight forwards, by a fissure 

 deeper and longer than that by which the first and the second 

 teeth are separated. The fourth teeth, or internal angles of the 

 upper orbital margin, are directed somewhat obliquely out- 

 wards. 



The first an tero -lateral tooth has a very characteristic form ; 

 it is truncated and slightly excavated at its external margin, 

 as in G. cruciferum ; but it projects much more forwards than 

 in that species, as will be seen by a comparison of figs, 1 & 2 

 PL V. ; the second tooth is about the same size as the first, 

 but is never larger than it, and it is rather acute, although 

 without a dark point. The four posterior teeth are dark- 

 pointed and acute ; the third, fourth, and fifth teeth are directed 

 straight forwards, but the last transversely outwards and 

 slightly forwards. The last tooth is also a little longer than 

 the anterior ones. Like the frontal teeth, those also of the 

 antero-lateral margins are much depressed and flattened. The 

 postero-lateral regions resemble those of G. cruciferum, and are 

 concave. 



The shape and the size of the internal lobe of the lower orbital 

 margin are also characteristic of this species ; for this lobe pro- 

 jects a little more forwards than the internal lobe of the upper 

 margin of the orbits, while in G. cruciferum the latter projects 

 more forwards than the former. 

 The subhepatic regions are hairy. 



The anterior legs are quite similar to those of G. cruciferum, 

 in the relative length of the arms and chelae and in their form 

 and armature. The anterior margin of the arms presents three 

 spines ; the wrist is armed with a long spine at the internal 

 angle, and with three small acute spines at the outer surface. 

 The outer surface of the hands of G. affine presents two longi- 

 tudinal minutely granulated crests near the smooth convex under 

 margin, and between the upper margin and the ridge which 

 is continued upon the immobile finger ; in G. cruciferum only one 

 crest is found on this place. The external surface of the hand 

 of G. affine has therefore three, whilst that of G. cruciferum has 

 only two, longitudinal crests. The outer and upper surfaces 

 of the hands of G. affine are covered with short hairs ; whereas 

 in this specimen of G. cruciferum these surfaces are perfectly 



LINN. JOTJaiSr. — ZOOLOGY, TOL. XSII. 6 



