144 



make up to the end of the carpus, which is distally expanded to support a very 

 large hand and chelae. 



The 4th and 5th pairs of legs end in a simple falcate dactylus of good length 

 and have the carpus and propodite obscurely divided into a few longish 

 segments. 



Abdominal appendages behind the 1st pair, biramous. 



The branchial formula is as follows : 



Total 1 + 7 ep. 566 =18 + 7ep. 



Engystenopus only differs from Stenopus in having the carapace practically 

 non-spinous and the dactyli of the last two pairs of thoracic legs falcate and of 

 good length : the large chelipeds of the 3rd pair also differ considerably in 

 shape. 



The original definition of the genus erred in stating that the carpus and 

 propodite of the last 2 pairs of thoracic legs are simple : they are obscurely 

 segmented, not, as in Stenopus, being multiarticulate, but being divided into a 

 few long segments. 



86. Engystenopus palmipes, Alcock and Anderson. PI. II. fig. 3. 



Engystenopus palmipes, Alcock and Anderson, Journ. Asiatic Soc. Bengal, Vol. LXIII. pt. 2, 1894, p. 149, pi. ix 

 fig. 1. 



ILLUSTRATIONS OF THE ZOOLOGY or THE INVESTIGATOR, CRUSTACEA, PLATE XXVI. FIG. 3, AND PLATE L. FIG. 5. 



Entire surface, except for a few definitely situated spines, chiefly on certain 

 of the appendages, perfectly smooth and polished. 



The carapace, measured in the middle line without the rostrum, is about 

 half the length of the abdomen : its frontal border on either side of the rostrum 

 is, like the posterior border, strongly emarginate, and is armed at each antero- 

 lateral angle with a pair of small spinelets : its regions, with the exception of 

 the gastric, are ill-defined. The rostrum, which reaches to about the middle 

 of the second joint of the antennulary peduncle, has a slight double curve : its 

 concave upper border bears numerous very close sharp equal serrations, and its 

 convex lower border has a single spine large enough to make the rostrum, when 



