INSECTS IN RELATION TO MAMMALIA. 5.">7 



known, inhabits the horse, particularly beneath the tail and in the 

 softer parts; the genus Melophagus, Lat. (Mclophila, Nitzsch), is also 

 only known by one species, the M. ovinus, which inhabits the sheep, 

 among the downy hair ; the only species of the genus Lipoptena, Nitz. 

 (Melophagus, Autor.), namely, L. Cervina (Pediculus cervi, Autor.), 

 frequents the different species of deer, and the genus Nycteribia the 

 bats, particularly the membrane of the wing. 



The remarkable family of (Estrodea, of which we have before made 

 frequent mention, live in their larva state parasitic upon the hoofed 

 quadrupeds, especially the Ruminantia, and they quit the animal when 

 they change into pupae : this takes place in the earth ; but the flies, 

 which must be numerous, to judge from the multitude of larvae, are 

 seldom visible ; and we are as yet ignorant upon what they live. But the 

 parasitic larvae are deposited by the fly upon the skin of the animal as 

 eggs, and bore through it when, as is the case with CEstrus bods and 

 (E. taranfli, they live beneath the epidermis ; or if they live in the 

 viscera of the animal they are conveyed in either by suction or licking. 

 The animals most subject to them are oxen, whose skin this fly pierces 

 and deposits its egg therein, the larvae here cause swollen excrescences, 

 from which their tails project, that they may respire. Another species, 

 the Gastrus pecorum, lives, according to Fabricius, in the intestines of 

 oxen. The sheep is still more tormented, which receives a species 

 (CEstrus mis) into its nostrils and temporal cavities. The giddy sick- 

 ness of sheep, which has been attributed to this larvae, may doubtlessly 

 be more correctly ascribed to the worm (Ccenurus cerebralis] living in 

 its brain, whereas these larvae are the cause of the sneezing, from which 

 many sheep suffer in summer. But the horse is chiefly annoyed by 

 these parasites : one species, the Gastr. nasalis, dwells in its oeso- 

 phagus ; a second, G. equi, and third, G. salutarius, in its stomach ; a 

 fourth (G. hcemorrhoidalis) even in the colon. The larvae hang here, 

 holding by means of their hooked mandibles, in rows, and look like 

 thick, blunt, long cones, which are surrounded at the apex by many 

 rows of spines, and at the base have two kidney- shaped horny lamina? 

 at their stigmata. The deer besides is tormented by the CEstri ; one 

 species, CEstrus tarandi, lives beneath the skin of the rein-deer, like 

 CE. bovis in the ox, whereas (E. trompe inhabits the temporal cavities 

 of the rein-deer. This fly is also found in Saxony, so that it is probable 

 that it also inhabits other species of deer. It is certain that (Estrus 

 lineatus, Meig., which, according to Schrank, hangs from the superior 



