290 Mr. Clark' J Qbfervat'wns on the Genus Oe/lrus, 



If the prefent inveftigation ftiould prove acceptable to the fcieii- 

 tific naturalift, from the fpecies being exhibited with greater per- 

 spicuity than they have hitherto been ; it is alfo hoped the de- 

 scription of their economy and manners will render it not lefs fo 

 to the enlightened veterinarian, as tending to point out the molt 

 eifedual means of removing them when they become the fource of 

 difeale. 



The obfcure fituation of the Oejlri in their larva ftate has been 

 a principal caufe of their hiftory being lefs underftood than that of 

 other infefts ; and in fome inftances the defe6live parts have been- 

 Supplied from imperfe6l obfervation, or mere conje<[:lure ; as the 

 CE. hicmorrhoidaiis is faid to depofit its eggs " mire per atmm intram^" 

 which, though perfe6tly fabulous, has by frequent repetition on 

 fuch high authority*, obtained the appearance of an eftabliflied 

 truth ; and from the filence of authors on the fubjeft, it appears 

 that the mode in which the other fpecies depofit their ova h^s not 

 been at all underftood. ""■•'! 1'- 



Since the time of Linnaeus the errors of this genus, far from being 

 expunged, have confiderably accumulated by the confufion of the 

 fpecies with one another ; which in part may be attributed to in- 

 attention, but chiefly perhaps to the difficulty of procuring Spe- 

 cimens for examination. The inacceffible Situations of the larva, and 

 the impofSibility of fuccefsfuUy imitating by artificial means their 

 mode of life when removed, have rendered them fcarce ; and in their 

 fly ftate they are not often Seen, or eafily taken. This difficulty 

 will be in a confiderable degree removed, when their hiftory and 

 the moft proper time of obtaining them is pointed out. 



The errors will be beft corredled by means of a plate, reprefenting 



• Linnai Syjlema Nattirx, p. 969. This error appears to have originated with Reau- 

 mur, who received it from a Dr. Gafpari. See note on CE. hiemorrhoidsilis. 



all 



