LARVAE OF SERGESTES 



25 



Elaphocaris 3 (Fig. 15 b). Length i-86. Rostrum i-omm. 



Rostrum much shorter in proportion than in stage 2, but about as long as carapace. 

 Supraorbital, lateral and posterior processes very hispid. Supraorbital longer than eye. 

 Telson as in stage 2. Abdominal somites with very small pleural spines, and with very 

 small dorsal points. 



Eye about three-quarters length of carapace, the eyeball asymmetrical. Papilla not 

 seen in dorsal view. 



Colour. Red in rostrum, and two lines down thorax and abdomen. In stage 3 there 

 is also red in posterior dorsal process and at base of telson. 



A 



/ V 



Fig. 16. S. ciassiis. Elaphocaris 2, ventral. 



A, frontal sensor)' papilla; B, ocular papilla; 



C, maxillule; D, maxilla; E, maxillipede i; 



F, maxillipede 3. 



Fig. 17. S. crassus. Acanthosoma i ; 

 a, antenna; b, telson. 



Acanthosoma i (Fig. 17 a, b). Length 2-55 mm. Rostrum 0-85 mm. 



Rostrum very spiny, with large basal spine. Supraorbital spines very small. One 

 pair of small lateral spines. Margin of carapace with a row of spinules continuous with 

 the spinules of the lateral spine. Dorsal organ very small. No posterior dorsal spine. 



Abdominal somites with dorsal spines i and 2 smaller than 3-6, which are subequal. 

 No ventral spines. Lateral spines short and prickly, decreasing backwards; that of 

 somite 5 very small. Telson short, nearly as wide as long, but posterior fork with very 

 long slender arms. These arms nearly parallel and reaching beyond the uropods, bearing 

 two inner and two outer spines. The lateral spine of the telson is inserted just beyond 

 the fork, on the arm itself. 



Eye one-fifth length of body, the length not quite i^ times width of eyeball, which is 

 slightly asymmetrical. No papilla seen on eyestalk. Antennal scale very broad near end, 

 and of characteristic shape (Fig. 17 a)\ flagellum short, not much longer than scale, 



