88 
Mr. Clark’s Appendix to a Treatise 
these insects in nature, I was at no loss to discover in this (E. lineatus ray old 
acquaintance the CE. Boris, the grand stumbling-block of naturalists. Hie 
ribs and furrows on the thorax, whence De Villars named it lineatus , pio- 
claimed it to be the same, and his figure, for he has given us an engraving ol 
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 carnarice ; caput 
facie subinflata pallidum, vertice, oculis, antennis, papillaque oris fusco nigti- 
cantibus ; collum excentricum, ori approximatum. Corpus glabrurn ; thorax 
supra opace niger punctis atris quatuor parium, duplici serie tiansveisa posi- 
tis, quorum media antica oblongata. Scutellum prominulum apice pilis spar- 
sum. Abdomen atrum, polito-nitidum, subtfis opaco-variegatum. Pedes pilosi, 
nigri. Alte fuscse basi margineque crassiori lutescentes, puncto exiguo disci, 
lituraque parva ad basin, nigris. Squamse subalares albse; halteres albo ca- 
pitulo.’ ” 
It would appear from Pallas and the American naturalists, that this singulat 
tribe of insects, the Cuterebrce, 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 tound 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 I ransactions, 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 
