54 



DISCOVERY REPORTS 



process stout, with 15-18 spines. Posterior process with six pairs of spines. Eye large, 

 asymmetrical, greatest diameter of eyeball more than half eye length. Somites of 

 abdomen with sharp pleural spines. 



Colour. These three stages are colourless, or with a yellowish tinge. 



Fig. 45. S. vigilax. a, Elaphocaris i ; b, Elaphocaris 2; c, Elaphocaris 3. 



Acanthosoma i (Fig. 46 a). Length 2-35 mm. Rostrum o-6 mm. 



Rostrum longer than antennules, with large basal spine. Supraorbital spines longer 

 than eyes ; hepatic spine rather large. Two pairs of lateral spines, of which the second 

 is small and the first reaches about to end of eyes. Posterior dorsal spine small. Dorsal 

 organ absent. 



Abdominal somites i and 2 with small median ventral spines; lateral spines short, 

 with small spinules, and a rather large backwardly directed basal spine, lateral spines 



