LARVAE OF SERGESTES 



57 



Abdominal somites with dorsal spines, the first two very small. Pleura with small 

 points. Somites i and 2 with ventral spines. Telson not quite twice as long as wide, 

 with very small distal fork. 



Eye more than one-quarter length of body, and diameter of eyeball more than half 

 length of eye. Labrum without spine. Antennal scale nearly 20 times as long as wide ; 

 flagellum 7-3 mm. long in a specimen of 3-2 mm. Mandibular palp absent. 



Fig. 49. S. vigilax. Mastigopus 2. 



Fig. 50. S. vigilax. Petasma. a, specimen of 1094 mm.; b, 14 mm.; 

 c, 16-3 mm., left, from inside; d, the same, from outside. 



Stage 2 retains all the spines of stage i almost without diminution. 



There seems to be much variation in the degree to which the exopods of the legs are 

 retained. Of three specimens moulted from the Acanthosoma one has no trace of exopods, 

 one has minute vestiges, while the third has long exopods even on legs 4 and 5. Pleopods 

 long, uniramous. Setose part of uropod rather more than half length of bare part. 



Colour. Body largely colourless, but with bright red patches in eyestalk, at base of 

 rostrum and in thorax. 



