-flps 



SUPPLEMENT. 



As stated in the introduction to the present Report, a few 

 pages are here devoted to some of those insects which liave come 

 under my observation, wdiicli do not pertain to tlie noxious class 

 but are yet too interesting on various accounts to be withheld from 

 the public. The limits, however, to which I find myself restrict- 

 ed oblige me to omit several species which I had purposed 

 noticing. 



210. Emasculatixg BOT-FLY, Cutevebra emasculator, new s-pecies. (Diptera. 

 (Estridas.) 



The history of this remarkable insect will be best presented by 

 extracting from my manuscript notes the successive memoranda 

 therein entered relating to this subject. 



August 13th, 1856. Peter Reid of Lakeville informs me that 

 his cat yesterday brought into the house a striped squirrel {Sci- 

 urus striatus.) On taking it into his hands he noticed its scrotum 

 was enormously s woollen and hard, with an orifice in it about the 

 size of a wiieat straw, and on pressing it with his fingers he could 

 distinctly feel the writhings of something alive in this tumor. On 

 enlarging this orifice with the point of a pen knife he discovered 

 it was a large grub lying with its tail to the opening. It dis- 

 charged at intervals three large drops of a fluid resembling gru- 

 mous blood mixed with purulent matter. On pressing upon it so 

 as to protrude the tail end of its body slightly out of the open- 

 ing it exerted itself to crawl out, forcing its fluids into the part 

 wdiich w^as out of the orifice so that it became swollen and hard, 

 and then regurgitating them into the body again, wdiereby the 

 extruded portion became soft and collapsed, thus pressing upon 

 and dilating the orifice, so that with three or four repetitions of 



