28 S Mr. B racy Clark on a new Species of Cuter ebr a. , 



wonderfully kept from such an increase as would be fatal to 

 the animals they feed upon, by the difficulties and imminent 

 hazards they are exposed to in the act of depositing their eggs. 

 The teeth of the horse must destroy, one should imagine, nine- 

 tenths of the CE. Equi, ktzmorrhoidalis, and salutiferus. The 

 (Estri seem however, in the hands of Providence, to make a 

 double recompense for the sufferings they occasion ; first, by 

 keeping the animals on the alert during hot weather, when 

 they would be often too idly disposed for their welfare; while 

 the few larvae which succeed in getting into their bodies, ap- 

 pear to benefit them by their local irritations, stimulating the 

 stomach to a quicker digestion of their watery food, and di- 

 verting diseases by their counter irritations of the skin and 

 frontal cavities, — thus producing the effect of issues or vesica- 

 tories, which are powerful remedies in relieving and in pre- 

 venting diseases. 



I apprehend that I have now sufficiently shown that the 

 (Estrus of the ancients could have been no Tabamis, and that 

 it is clear Olivier, who appears to have originated this notion, 

 and who was followed by Latreille, was mistaken. 



A very extensive enumeration of this genus is seen in a late 

 ingenious publication, the Systematische Beschrcibung of J. W. 

 Meigen. It is however in some instances not correct ; for on 

 carefully examining the (Estrus lineatus of this writer, intro- 

 duced from Villers, it would appear to be that stumbling- 

 block of systematists in entomology, the CE. Bovis of my enu- 

 meration*, and not of Linnaeus, as he states, who, as we have 

 repeatedly said, described the CE. Equi for this species. The 

 (E. pictus of this author, beautifully figured by Curtis in the 

 British Entomology, no. xxvi. 1. 106, 1 rather suspect to be the 

 faucial bot of the Stagf. 



As the species of the new genus Cuterebra were taken for 

 (Estri till I separated them, and are closely allied to them in 

 their habits, I have ventured at the close of this paper to com- 

 municate to the Society a new and undescribed species lately 

 received from America, along with some other insects sent me 

 by my nephew, Joseph Clark, from the Illinois. 



* The lines on the thorax, and the figure of Villers, undoubtedly con- 

 firm it. Meigen's CE. Bovis is the CE. Bovis of my enumeration, under 

 which this should have come as a synonym. 



f I may here observe, that a few days since, in visiting the British Mu- 

 suem, I was shown the insect Dr. Leach has called CEstrus Clarkii, and 

 find it only a variety, and scarcely that, of the CEstrus veterinus of my 

 enumeration. 



Cut- 



