29 



sMict^ its liost is coiiiiuoii in llic State there is searei'ly any doubt 

 hilt llitit it is tliere and ean be found at the proper season. An- 

 I'Mier s}>eeies of this same jreniis, oecurrinfr in Europe, is known 

 If liavi' similar liabits. 



Tliei'e are a niuiibcf (>r other sj)eeies of I lynK-noplei-a that 



liiive been ol)served to be natural enemies of the horseflies, and 



these, as well as the ones mentioned, should receive further study, 



* SM iliat the benefits derived from them will be bettei- understood 



;>i(l the p(»ssil)iliti(^s of utili/inji' them i-ealized as far as possible. 



tup: K0BBEK-KMK8. 



These bi'lonu' to th<^ order Diptera. as do the h(U-sef1ies. The 

 r, bt)<'i--Hy known as Era.r lateralis INIacfjuart is eommon Avher^? 

 f have been in Louisiana, and is a regular hawk among insects^ 

 f KMjuently capturing the smaller members of the genns Tahanus, 

 a well as other insects. It does not appear, howevin-. that the 

 r'>bber-Hies ai'e of as much importance in this connection as the 

 \\as]>s. foi- the reason that the adults do not attend their larvae 

 • hiring growth, and hence capture insects for their own food 

 <»rdy. As the robber-fly larvae are predaceous and live in the 

 ground, they have an opportunity to capture other larvae that 

 live in sucli situations, and therefore they may devour an oc- 

 <'.-'sional immature hr)i'sefly. 



Ther(^ are scores of species of large flies l);'longing to the 

 s.-urie family as the one just named, and all of theni procure their 

 f< (»d in th(^ s;uiie way that it does. They ai-e cunning insects, re- 

 I'laining jX'rfectly (juiet in some inconspicuous place until an 

 irtseet that they desire for food comes close enough, when they 

 pounce upon it and by means of their strong legs, which ar.^ 

 provided with sliarji claws, retain it until they introduce 

 their mouth parts and syck away its life-blood. Species of the 

 genus I>( ro}iiyia were especially conspicuous in the fields in the 

 vicinity of the (iulf l-Jiologic Station, and they \\('re often seen 

 <■: pturing horsetiies for food. 



In a complete report on the mitural enemies of hitrsetlies. 

 ihe lai-ge di'agon Hies and vai'ious species of Ilemiptera. or true 

 1 I'gs. should rec<'ive consideration. Spid(M's often catch the adult 



