SOUTH AP'RICAN EAGWORMS. 647 



mow bears one seta (6) while group 7 has increased to its 

 normal number of three setee, instead of two as in the previous 

 .instar (fig. 6). On abd. segments 1 and 2 these are divided, 

 «o th;it one of them is implanted on the enlarged mid-ventral 

 plate and the other two on the small wart corresponding with 

 the leg-plate in the proleg bearing segments. The hooks on 

 the abdominal prologs have doubled and range now from 18 

 to 20 in number (fig. 6). These ai-e placed in a single loop, 

 not entirely closed, the opening facing medio-caudad. Abd. 

 7 resembles that of the first instar, except for the appearance 

 of seta3 6 (fig. 5). Abd. 8 shows the dorsal plate now 

 divided in two halves, widely separated in the median line, 

 and the development of the seta 6 as on the preceding 

 segments. On abd. 9 the dorsal plates are also widely 

 separated in the median line, the subspiracular plate is split in 

 two, each bearing one seta, while in addition there has 

 appeared on the subventral plate a seta 6. On abd. 10 

 the arrangement of the setae on the anal plate has remained 

 the same, the anal legs have acquired a posterior leg-plate 

 with four strong setae and on the lateral leg-plate group 

 7 now consists of three setas as on the other abd. segments. 

 Hooks of anal prologs doubled, and these are now 16 to 18 in 

 number. 



Third Instar. 



Length of larva 9 mm. (rround colour of caterpillar pur- 

 plish vinaceous (XXXIX). Head, pattern on prothoracic 

 shield, thoracic shields, thoracic plates, legs, anal plate and 

 leg-plates on anal prologs, hooks and abdominal prologs 

 chestnut brown (XIV), setiferous plates on abdominal seg- 

 ments cinnamon brown (XV), ground colour of thoracic 

 shields salmon buif (XIV), body more flattened dorso- 

 ventrally, with the greatest width at the caudal edge of 

 the second abdominal segment. 



Head. — Width of head-case 1*7 mm. Suture between 

 parietals and adfrontals now indicated, especially on the 



VOL. 3, PART 3. 43 



