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a deep median groove into two lateral lobes each of which bears a rudimentary 

 bell-shaped antenna. 



All the segments bear black chitinous hooks with the points directed 

 backward. On the cephalic and prothoracic segments are several series of 

 hooks, but on the remaining segments, these are smaller and fewer in number. 

 Each of the intersegmental grooves of the abdomen is margined by hooks 

 whose points are oppositely directed on each side of the groove. 



The larva is metapneustic at this stage, the post-abdominal spiracles being 

 terminal. These communicate with two lateral tracheal trunks. 



The mouth-parts differ considerably from those of the later stages. The 

 cephalo-pharyngeal sclerite is strongly chitinised, its posterior margin being 

 deeply embayed. Anteriorly it is prolonged as a slender bar and terminates 

 in a wedge-shaped vertical plate which protrudes from the mouth. Ventro- 

 posteriorly to this terminal wedge, there lies a free sclerite which is probably 

 homologous with the dentate sclerite of the second and third stage larvae 

 (PI. XIV, fig. 10). 



The Second-stage larva is about 3 mm. long (fig. 3). All the segments 

 bear small chitinous hooks, so directed that each intersegmental area is 

 bounded by two sets of hooks, one set pointing backward, the other forward. 

 These hooks are few in number, each segment bearing only one or two rows. 

 Besides these all the segments bear several series of blunt transparent spines. 



The prothoracic spiracles (fig. 25) terminate in five or six papillae. The 

 post-abdominal spiracles are borne on two tubercles, each having three clefts 

 surrounded by peritremes. On the outer border of each peritreme lies a white 

 spot, the opening of the perispiracular gland (figs. 18 and 19). 



The bucco-pharyngeal apparatus is similar to that of the third-stage 

 larva but only half the size (fig. 11). 



Third-stage Larva. The full-grown larva, when ready to pupate, is about 

 8-5 mm. long and 1-75 mm. in diameter. There are two cephalic segments, the 

 first bearing rudimentary bell-shaped antennae while the second on its ventral 

 surface bears a patch of backward pointing chitinous hooks. Behind the cephalic 

 segments, eleven segments can be distinguished. Of these three are probably 

 thoracic and eight abdominal. On the ventral surface these segments bear 

 two series of similar hooks, one on the anterior margin pointing backwards, 

 the other on the posterior margin pointing forwards. Each intersegmental 

 groove is therefore bounded by two series of hooks pointing in opposite 

 directions. These hooks are of two kinds — small, sharp and chitinous, and 

 large, blunt and transparent. The small chitinous hooks are borne on the 

 second cephalic segment and on the last three abdominal segments where they 

 are directed forward (fig. 4). 



The tracheal system consists of two longitudinal trunks, united posteriorly 

 by a commissure, having along their length branching lateral tracheae. 



The prothoracic spiracles, which emerge on the anterior margin of the 

 first thoracic segment, are fan-shaped with from six to eight lobes. In some 



