43 

 Gastrophilus cqiii, Fab. (Common Horse Bot). 



This fly is common at certain seasons around stables and on 

 horse ranches, where they may be observed darting at the flanks, 

 legs or mane of the animal. Aided by the pointed abdomen they 

 deposit their eggs thereon, each of which are securely attached to 

 a hair. These yellowish-white eggs contain larvae, which are 

 licked up by the unfortunate animal and thus conveyed into the 

 esophageal tract, whence they travel into the stomach, sometimes 

 occurring in such numbers as to cause the death of the host. 

 Upon passing from the horse the fully-fed larvae (which are 

 about three-quarters inch in length) pupate either in the manure 

 or earth. 



The adult is somewhat bee-like in size and form, of a tawny- 

 brown color with dark patches on the thorax and abdomen, the 

 whole body being densely covered w^ith short fine hair. The 

 wangs are yellowish w^ith darker patches. 



One practical remedial measure has suggested itself to many, 

 that is, to scrape (or shave) ofif with a shatrp knife the 'eggs; 

 this should be repeated at frequent intervals (three or four days) 

 during the egg-laying period. 



Oestrus oiis, Linn. (Sheep Bot or Head Maggot). 



This fly appears to be present on the sheep ranches here, al- 

 though personally the writer has not seen it. 



The eggs are deposited in the nostrils of the shee'p, the larvae 

 soon hatch, travelling up the nasal passages and entering the 

 frontal sinuses, where they remain until attaining maturity; they 

 then descend via the nasal passages and pupate in the soil. 



The adult insect is similar in general appearance to that of 

 the horse-bot, but greyer and much smaller. 



Hypodcnna sp.? (The Ox Bot or Warble). 



To what extent warbles occur on these islands I do not know, 

 but they are certainly present. The species obtained has not 

 been definitely identified. These flies are bee-like and hairy, 

 bearing a general resemblance to the horse bot ; the coloring of 

 the body, however, differs from the former insect. The head and 

 thorax being covered with rich golden brown hairs, the abdomen 



