INDIRECT INJURIES CAUSED BY INSECTS. 121 



but probably such a manoeuvre is unnecessary, since there seems no rea- 

 son, supposing the eggs to be laid in the nostrils, why the larva when 

 hatched cannot itself make its way down to the above station, as easily 

 as that of the sheep into the maxillary sinuses. Or, which perhaps is more 

 likely, when the animal draws in the air, the eggs or larvas may be carried 

 down with it, in both cases, to the place assigned to them by Providence.^ 

 No animal, however, is so cruelly tormented by (CEstri as the rein-deer ; 

 for besides one synonymous apparently with this of the deer ((E. nasalis), 

 from which they endeavor to relieve themselves by snorting and blow- 

 ing^, they have a second which produces hots under their skin ; not 

 improbably the same species that in a similar way attacks the latter, as I 

 have stated above. We have heard that the vaccine disease is derived 

 from the cow and the horse, and the small-pox is said to have originated 

 in the heels of the camel : but neither the ingenious Dr. Jenner nor any 

 other writer on this subject has informed us that the rein-deer is subject 

 to the distemper last named ; yet Linne quotes the learned work of a 

 Swedish physician on Syphilis, who gravely gives this as a fact ! !^ The 

 inoculator, in truth, is the gad-fly, the tumors it causes are the pustules, 

 and its larvae are the pus. — It is astonishing how dreadfully these poor 

 animals in hot weather are terrified and injured by them : ten of these 

 flies will put a herd of five hundred into the greatest agitation. They 

 cannot stand still a minute, no not a moment, without changing their pos- 

 ture, puffing and blowing, sneezing and snorting, stamping and tossing 

 continually ; every individual trembling and pushing its neighbor about. 

 The ovipositor of this fly is similar to that of the ox-breese, consisting of 

 several tubular joints which slip into each other; and therefore Linne was 

 probably mistaken in supposing that it lays its eggs upon the skin of the 

 animal, and that the hot, when it appears, eats its way through it^: there 

 can be little doubt (or else what is the use of such an apparatus ?) that it 

 bores a hole in the skin and there deposits the eggs. About the begin- 

 ning of July the rein-deer sheds its hair, which then stands erect — at this 

 time the fly is always fluttering about it, and takes its opportunity to ovi- 

 posit. The bots remain under the skin through the whole winter, and 

 grow to the size of an acorn. Six or eight of these are often to be found 

 in a single rein-deer that has seen only one winter ; and these so emaciate 

 them, that frequently one third of their number perish in consequence. 

 Even those that are full-grown suffer greatly from this insect. The fly 

 follows the animals over precipices, valleys, the snow-covered mountains, 

 and even the highest alps ; to which, in order to avoid it, they often fly 

 with great swiftness in a direction contrary to the wind. By this constant 

 agitation and endeavor to escape from the attack of their enemy they are 

 kept from eating during the day, standing always upon the watch, with erect 

 ears and attentive eyes, that they may observe whether it comes near 

 them.^ The rein-deer are teased also by a pecular species of Tabanus 



' For the account of the (Estrus, of the deer, see Reaum. v. 67 — 77. 



^ Linn. Lack. Lapp. ii. 45. In the passage here referred to, Linne speaks of two species 

 of CEstrus, though the mode of expression indicates that he considered them as the same. 

 One was CE. jiasalis, from which they freed themselves by snorting, dec, the other CE. 

 Tarandi which formed the pustules in their backs. In Syst. Nat. 969. 3. he strangely ob- 

 serves under the former species, " Habitat in equorum fauce, per nares intrans ! " confound- 

 ing probably CE. veterinus of Mr. Clark with the true (E. nasalis. 



3 Lack. Lapp. i. 280. * Flor. Lapp. 79. * Linn. Flor. Lapp. 379. 



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