341 



V. siq)rasfi(/iu(tlis is largo, just as v. infrastigmalis. Tlio setae 

 of these tubercula are ± 2'/.2 mni. long. V. hasalis is small. 

 S('(/iti. 3, 4. V. (for,s'«//ö' is absent, the 'V. si(hdorsales of the left 

 and right sidos have coalesced. They have setae as those 

 of seffment 1, bnt are a little shorter and are white in 

 colour. For the rest as in instar IL 

 „ 5. F. dorsalis is absent, the other tubercula as in instar II. 

 „ G, 7 as in instar II. 



„ 8. The two V. subdorsales of the left and right sides are 

 united, but not coalesced. They project high er than in instar II. 

 The setae elosely resemble those of the segments 1 and 2. 

 „ 9, 10. V. infrastigmalis of 10 remains large. 

 Instar IV. Duration 8 days. Length 15 mm. 

 FroiJiorax. V. (lorsalis is small and is now to bc found as a 

 protuberance placed in the median line on the base of the strongly 

 developed v. suprastigmalis. On its top is a black spot on which 

 are implanted short plumed setae, ib 3^/, mm. long and two 

 tufts of plumose setae viz. + 1 — Vj^ mm. and + 2^\., — 3 mm. 

 long. Each group consists of +6 — 10 setae. There are no tran- 

 sitions between these two, so that they clearly form two storeys. 

 The longest ones also have the largest side branches. The other 

 tubercula are as in instar ///. 



Mesothomx and MetatJiorax. As in instar IJl but v. dorso- 

 lateralis has grown smaller. 



Abdomen 1, 2. The four warts which in instar III began to 



coalesce, now form a whole. Tor the rest as in instar III. 



Secjm. 3, 4 = 1. It should be observed that here v. dorsalis has 



not been united with the median shield, but has disappeared. 



The colour and the form of the setae now agree with 



those of segment 1. 



The other warts on this segment and on the following 

 segments correspond with those of instar /// but : 

 „ 8. The two r. subdorsales are almost united and between 

 the many plumed setae some plumose ones are found as 

 on the prothorax. 



22 



