CETJSTACEA OF THE MERGTJI ARCHIPELAGO. 91 



running obliquely forwards from the posterior margin of the 

 cephalothorax, and parallel to the postero-lateral margin, almost 

 to the level of the last antero -lateral tooth. 



A little behind the frontal margin two slight transverse 

 elevated lines are observed on the upper surface of the cephalo- 

 thorax between the orbits ; these epigastric ridges are separated 

 from one another by a faint mesial frontal furrow, which is bifur- 

 cated behind as usual. Two other transverse ridge-like eleva- 

 tions are found on ^each antero-lateral region, the anterior of 

 which is situated at the base of the tliird antero-lateral tooth ; 

 whereas the posterior, parallel to the anterior, is found at the 

 base of the fourth antero-lateral tooth. The anterior of these 

 transverse ridges and the transverse epigastric ridges are united 

 on each side by a ridge- lite elevation which runs parallel to the 

 upper orbital margin. The cervical suture which separates the 

 gastric from the cardiac region is very faintly marked. An 

 impressed line proceeds close to and parallel to the posterior 

 margin of the cephalothorax. The rest of the upper surface of 

 the cephalothorax appears quite smooth and glabrous, slightly 

 convex anteriorly and flattened posteriorly. 



In Eucrate affinis the endostome is more distinctly longitudi- 

 nally ridged on each side than in E. crenata ; but in the form 

 of the epistome and of the anterior margin of the buccal cavity, 

 both species resemble one another. The male abdomen is seven- 

 jointed, scarcely narrower towards the base than the contiguous 

 part of the sternum ; the third joint is the most enlarged ; 

 and the remaining terminal part is very narrow, the joints gra- 

 dually increasing in length and decreasing in breadth, so that 

 the terminal joint is the longest of all. I have only a female 

 specimen of E. crenata before me, and I am therefore unable to 

 decide whether both species agree with one another as regards 

 the form of the male abdomen ; but the female abdomen presents 

 precisely the same form in both species. 



The anterior legs are subequal, the right being in all the spe- 

 cimens a little larger than the left ; they have the same form 

 and size both in the male and in the female. The anterior 

 as well as the ambulatory legs are closely similar to those of 

 E. crenata. 



The upper margin of the arms is armed with a strong tooth near 

 its distal end, which is " separated distally by a transverse groove 

 from a second, lower, transverse elevation," as Haswell rightly 



