i68 



INSECTS 



experience is a little the most satisfactory and agree- 

 able. The odor is offensive to others, however, and 

 these may find the menthol preparations more satis- 

 factory. Cattle and animals not being able to resort to 

 repellants often suffer cruelly, and in countries where 

 buffalo and similar larger gnats are plentiful, they 

 are sometimes driven literally insane by the pain and 

 irritation of the attack. 



The early stages being 

 passed continually under 

 the water surface, offer no 

 points for an attack with 

 oils. No matter how the 

 upper layer may be coat- 

 ed, the insects on the bot- 

 tom will be little or not at 

 all disturbed, and as they 

 usually inhabit running 

 streams, it is practically 

 impossible to maintain a 

 surface covering anyhow. 

 Those species that attach 

 themselves to logs and 

 sunken or surface-lodged 

 tree trunks or the like, may be mitigated by cleaning 

 out such obstructions and points of attachment; but 

 for such species as attach themselves to stones on the 

 bottom we have no remedy that is not also likely to be 

 fatal to fish and other forms of aquatic life. Thus far 

 no charge has ever been made against any of the 

 SimvdiidcB that they are carriers of disease in man or 

 animals ; but our actual acquaintance with the flies and 

 with the diseases of the animals that inhabit their ter- 

 ritory is slight, so that it would hardly be safe to say 

 that they are not dangerous in such direction. 



-Larva and pupa of buffalo 

 gnat. 



