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VoluccUii obesa, Fab. 



This fine fly is very common in the gardens around Honolulu 

 and may often be seen poised practically motionless in mid-air, 

 then darting- rapidly out of sight. In size it is about equal 

 to that of a honey-bee and stoutly built ; the upper surface is of a 

 brilliant metallic bluish-green, the ventral surface having a bright 

 purple sheen. 



I have not bred the larva, but it probably feeds in decaying 

 vegetation. 



Eristalis piinctulatus, Macq. 



This common hover-fly somewhat resembles a honey-bee in 

 form and size. The large eyes are of a reddish-brown. The 

 thorax pale buff, with four distinct longitudinal black bands. The 

 abdomen is tawny in the male, with dark transverse bands ; in the 

 female these bands are nearly black, and very distinct. 



The larvae is aquatic, living in stagnant and foul water, feed- 

 ing upon stable refuse or decaying vegetation, around which the 

 female flies may frequently be observed depositing masses of the 

 white slender eggs. The whitish larva is maggot-like and semi- 

 translucent, the digestive and other organs being easily visible 

 through the tough skin ; it belongs to that type known as "rat- 

 tailed," since it possesses a very long and protusile breathing- 

 tube, which is capable of being extended for nearly tv/o inches; 

 by this means the larva can remain hidden in the submerged mud 

 and continue its respiration unchecked. 



Xaiithograiiiiiia grandicorne, Macq. 



This pretty little hover-fly is extremely useful, since its larva 

 is a most voracious devourer of plant lice or aphides. The adult 

 which is about one-half inch in length niay frequently be ob- 

 served hovering over an aphis-infested plant, then with remark- 

 able rapidity she alights on a leaf, deposits a single Qgg, and is 

 gone, to repeat the process in some other suitable location. 



The eyes are large and reddish brown. The thorax a shining 

 steely-blue. The abdomen is a rich yellow with decided black 

 transverse bands. 



The eggs are white and the greenish or reddish slug-like 

 larvae are invariably present upon any plant infested with plant 



