72 



RECORDS OP THE AUSTRALIAN MUSEUM. 



and scarce, becoming more numerous and shorter towards the 



end of the antenna. 



Prelabial zone 

 distinctly shorter than 

 long, with a circular area 

 near the apex and 

 shortish setae disposed on 

 three rows placed 2, 2 

 and 5. Median plate of 

 labrum rather large, its 

 breadth being one-tenth 

 of the total breadth of 

 the labrum ; its surface 

 is uneven hut destitute 

 of t ee 1 1) or 1 a she s. 

 Lateral plates almost 

 twice as broad as long, 

 furnished with but few 

 lashes at the inner end 

 of its posterior edge. 

 Fulcri broad (Fig. 27). 



Mandible as in the 

 preceding species, but 

 without a blunt tooth at 

 the distal end of the 

 pectinate lamella. The 

 inner convex surface just 

 below the apex is 

 densely clothed with 

 delicate setae (Figs. 28 and 29). 



Coxosternum of first maxilla; undivided, 

 without lateral palpi ; coxal process long. Next 

 joint bearing a veiy small palpus. 



Coxosternum of second maxillae divided into 

 two halves which stand apart from one another. 

 Each half is divided into three distinct parts 

 which are considered homologous to the coxa, 

 the sternum and the pleura. The pleural plate 

 stands for itself, being surrounded with 

 membrane ; the sternal plate, in shape of a 

 narrow band, is almost entirely isolated by a membranaceous cleft 

 from the coxa with which it is fused only by its inner (anterior) 

 angle ; the metameric pore is concealed under the inner end of 



Fig. 29. S. rainbowi, Briilem. 

 maxilla), ventral view. 



Second 



Fig. 30. S. rain- 

 bowi, Brolem. 

 Inner margin 

 of maxillipedes. 



