HABITS, ETC., OF HYLEMY/A GRISEA, FALL. 



19 



Fig. 3. — Mature larva of Hylemyia grisea. 



hope to ascertain by further observations how the Hylemyia 

 larva reaches the pollen ball. I have never discovered 

 what is the fate of the bee grub for which the pollen 

 ball eaten by a maggot 

 was destined. If the 

 fly maggot hatches out 

 and commences to eat 

 the ball before its com- 

 pletion by the bee, it 

 may be well imagined 

 that no bee's q^^ would 

 be laid. Otherwise the maggot must devour the unhatched 

 egg or the young grub. That the dipterous egg is the 

 earlier to hatch out can hardly be doubted, since it is laid 

 during the manufacture of the pollen ball, while the bee's 

 sgg would not be deposited till after its completion. 



The LARVA of H. grisea is represented in Fig. 3 (the 

 specimen from which the drawing was made having been 

 preserved in alcohol had undergone some contraction). 

 A full-grown larva measures about 9 mm. The most striking- 

 character of this maggot is the great breadth of the hinder 



portion of the body. The cuticle is thin, 

 and very free from spines. There are 

 thirteen segments of a yellowish white 

 colour. Immediately behind the well- 

 developed mouth-hooks (Fig. 4) are the 

 minute two-jointed antennae (Fig. 4) and 

 the slightly more laterally placed sensory 

 spots (Fig. 5). The prothoracic spiracles 

 have thirteen stalked lobes (Fig. 6). 

 „:!^ The hind face of the last segment 

 Fig. 4.— Buccal-pharyn- exhibits the two distinct areas usual 

 geal apparatus of mature in the larviE of most Anthomyiidae, the 



larva, drawn from a , , , . . 



preparation cleared in oblique dorsal portion bearing the 



caustic potash, x about spiracular area, and a truncated anal 

 40. ^ ' 



region (Fig. 7). The three openings of 



the posterior spiracles are arranged in the form of a trefoil, 



and the spiracular area is surrounded by six pairs of fleshy 



pointed tubercles (Fig. 7). 



