26 



DISCOVERY REPORTS 



unsegmented, with four small apical setae and two marginal spines. Labral spine large. 

 Mandibular palp absent. Pleopods very small, simple. Uropods about seven times as 

 long as wide; bare part slightly longer than setose (i : o-86). 



Acanthosoma 2 (Fig. 18 a). Length 2-6 mm. Rostrum 074 mm. 



Scarcely differing from stage i. Antennal scale of same form, but with large 

 denticulate spine. Flagellum not extending beyond rostrum. Mandible without palp. 

 Pleopods very small, without endopods. Uropods unchanged. 



Colour. Vermilion down sides of carapace, on legs, antennule, antennal scale, and 

 distal part of exopod of uropod. 



Fig. 18. S. crassus. a, Acanthosoma 2; b, Mastigopus i. 



Mastigopus I (Figs. 18 6, 19 a-g). Length 4-15 mm. Rostrum 075 mm. 



Rostrum reaching end of peduncle of antennule; basal spine small. Carapace short, 

 its length about i\ times the breadth. Supraorbital spine very small; marginal spine 

 of Acanthosoma retained. Hepatic spine absent. Dorsal organ minute. Dorsal spines 

 of abdominal somites 1-3 very small, those of 4-6 larger. Pleura rather expanded, with 

 very small points. Telson twice as long as wide, with strong lateral spines; arms of 



