SOUTH AFRICAN BAGWORMS. 651 



the distance between base of clypeus and notch of vertex. 

 Parietals Avith distinct pattern as shown in text-fig. 2, a. 

 Mandibles with five teeth which are now blunt, the outer 

 two the larger. Labruni strongly cliitinised, median notch 

 rounded. Otherwise no change from the conditions in thet 

 previous instar. 



Thorax. — There is no change from the conditions in the 

 third instar except a stronger pigmentation and a more pro- 

 nounced pattern on the thoracic shields. 



Abdomen. — No differences in the ai-rangement of plates and 

 set?e as compared with the previous instar. The small rudi- 

 mentary seta in front of the spiracle (3rt?) present on all 

 abdominal segments. Number of booklets on abdominal pro- 

 legs irregular, varying between 18 and 22, on anal legs from 

 16 to 18. 



Fifth Instar. 



The larva reaches a length of 34 mm. Ground colour of 

 body on sides and ventral aspect of abd. 3-6 cinnamon drab 

 (XL VI), on back and ventral aspect of other abdominal seg- 

 ments fuscous black. Setiferous plates on abdominal segments, 

 hooks of prolegs and anal leg, fuscous black (XL VI) , anal plate, 

 anal leg-plates, markings on thorax and on head black. Ground 

 colour of head and anterior edges of thoracic shields argus 

 brown (III), giound colour of thoracic shields maize yellow 

 (IV). Spiracles xanthine orange (III). Thoracic legs fuscous 

 black (XLVI) with spots of maize yellow (III) on the coxae 

 and one subventral on the post coxal plates of the third tho- 

 racic segment. 



Head. — Width of head-case 4 mm. The pattern on the 

 head has undergone no radical change. 



Thoeax. — On the thoracic segments the pattern has become 

 more broken up, the light ground colour more pronounced, 

 especially on the second and third thoracic segments. On the 

 coxal plates the light spot has also appeared. The structure, 

 position of seta?, etc., otherwise agree with those in the fourth 

 instar. 



