88 Mr. Clark's Appendix to a Treatise • 



these insects in nature, I was at no loss to discover in this ffi". lineatus my old 

 acquaintance the (E. Bovis, the grand stumbling-block of naturalists. The 

 ribs and furrows on the thorax, whence De Villars named it lineatus, pro- 

 claimed it to be the same, and his tigure, for he has given us an engraving of 

 it also, fully served to confirm it. 



At page 16, line 18 of my dissertation, insert : "On examining the work of 

 Prof Pallas, 'Novae Species Quadrupedum e Glirium Ordine,' p. 50, I find 

 the description of an CEstrus infesting Lepus alpinus, to which he gives the 

 name of leporinus, and which would appear to belong to my genus Cuterebra. 

 His description of it is as follows : 'Totus ater subpiloso-glaber, facie alarum- 

 que margine crassiore lutescentibus. Magnitudine Muscce camarice ; caput 

 facie subinflata pallidum, vertice, oculis, antennis, papillaque oris fusco nigri- 

 cantibus ; coUum excentricum, ori approximatum. Corpus glabrum ; thorax 

 supra opac^ niger punctis atris quatuor parium, duplici serie transversa posi- 

 tis, quorum media antica oblongata. Scutellum prominulum apice pilis spar- 

 sum. Abdomen atrum, polito-nitidum, subtiis opaco-variegatum. Pedes pilosi, 

 nigri. Alae fuscae basi margineque crassiori lutescentes, puncto exiguo disci, 

 lituraque parva ad basin, nigris. Squamae subalares albse ; halteres albo ca- 

 pitulo.' " 



It would appear from Pallas and the American naturalists, that this singular 

 tribe of insects, the Cuterehrce, extend through all the northern and subnorth- 

 ern regions of the New and Old Continents ; and they appear in these coun- 

 tries to infest chiefly the hares, rabbits, rats, mice, moles, &c. My brother 

 sent me a small one of this genus from the Illinois, that had been found living 

 under the skin of a dead mouse : not probably that they feed on dead animals, 

 but this ferocious little larva, which he said had cleared the ribs of nearly all 

 their flesh, had resorted to such food from dire necessity; the animal having 

 died from some cause or other, and there being a cessation of further secre- 

 tion of pus, it was left with no choice but to do that or die. 



The above species described by Pallas is very nearly allied to, or the same 

 with, my C. fontanella, described in the Linnean Transactions, vol. xv. 

 p. 410, and figured in my Treatise, pi. 2. fig. 23. It is most probably an allied 

 species, as there appear some discrepancies on comparing the respective de- 

 scriptions. 



My late worthy and ingenious friend Latreille has written on this subject 



