Mr. Clark'j Ohfervailom on the Genus Oejirus. 323 



whofc generous liberality in promoting ufeful refearch by thjs in- 

 diipenlable aid can never be too much admired. 



The refuk of this enquiry has induced me with the greater rea- 

 dinefs to offer thefe remarks to the Society, from the irrecoucileablc 

 dcfcriptions and difficulties which will be found in the bed writer^, 

 who have endeavoured to defcribe the prefent genus. 



I have omitted the reference to Ray, becaule the defcription, if 

 meant for the CE. Equi, is hardly worth preferving. From the 

 " alis crebrh punclh^" one iliould fui-)pole the Tabanus pluvlalis was 

 intended by this defcription. 



From the obfcrvations of JVoblfarbt^ " De vermibus per nares ex- 

 cretis,'" it appears not improbable that the CE. Ovis, under a fa- 

 vourable opportunity, and perhaps deprived of its ufual nidus, had 

 depofited its eggs in the human noftril, as I know of no other 

 larva of this kind that could fuftain the temperature of that fitu- 

 atioti ; yet the figures given of the flies obferved by him do net 

 much refemble O.Jiri*, 



J. Leonhard Fifcher (Difpuiatio Inauguralis. Lipfia: 1 788) has 

 given an elaborate defcription of the CE. Bov'is and Ovis. 



In the Anfan^gritnde der Naiurgefchichle of Lejke, the laiva, tab. 9,. 

 fig. 19, is that of the Equi; while the fly (fig. 21) is the CE. Bovis. 

 De Geer, who for excellent defcriptions and general accuracy 

 furpafles, in my opinion, nearly all the wiiters on thefe fubjecls) 

 has rightly corrected Linnaeus by not confounding the Bovis and 

 Equi, but has unfortunately fallen into the error of confidering the 

 Bovis and the ha^norrhoidalis as the fame. Hijloire des InfeSies, p. 297. 

 Genera et Species Infe£lorum, p. 1-92. 



* Since the above was committed to the prefs. Dr. Lntham has informed me of a cafe 

 related in the firft; volume of tlie Medical Communications, in which infers were removed 

 from the antrum maxillare of a woman, and are evidently, as Dr. Latham has fuppofed, the 

 iarvx of the (E. Btvis. 



Tta In 



