THE MODERN HORSE DOCTOR. 417 



expel this are ordinarily ineffectual up to the period at which its 

 growth fits it for metamorphosis ; when, by squeezing the pus- 

 tule forcibly between the nails, a vermicular body springs livelily 

 out, as though impelled by elasticity, and rolls upon the ground. 

 This body is no other than the larva. 



" There can be no doubt but that these larvie feed upon the 

 pus which forms in the tumors that serve them as habitations up 

 to the moment of their transformation ; neither is there any that 

 the bristles clothing their body serve to augment the secretion 

 of the pus through irritation of the skin, no more than there is 

 doubt that the animal makes use of them, like the hypoderma of 

 the ox, for the execution of the motions required for his escape 

 from his foul abode. Once at liberty, he sets out in search of 

 shelter either in the earth or the dung, and therein, after having 

 remained for ten or eleven months underneath the horse's skin, 

 it changes into fly. 



" The larva that has been engaging our notice is comparative- 

 ly rare in the south, but frequently found in the northern parts 

 of France ; it is likewise common in Belgium and Holland, along 

 the entire shore of the Baltic and the North Sea. 



" Save the phenomena already detailed, the cuticular larva of 

 the horse occasions, according to M. Loiset, no appreciable mor- 

 bid derangement. Nevertheless, about the period of its full 

 growth, it appears to occasion some troublesome itchings, which 

 give way to lotions of cold water, at times slightly vinegared, or 

 else to some of the means employed for the destruction of the 

 larva of the hypoderma bovis. 



" How long does the state of fly continue ? "What are the 

 habits of the insect after it has arrived at its final transforma- 

 tion ? These two questions, as yet, wait for answers ; but it is 

 to be hoped they will not wait much longer. We have for guar- 

 anty of this the renowned seal of MM. the professors of our 

 Veterinary School, touching all that concerns the interest of 

 science of which those gentlemen are the worthy representa- 

 tives." — Translated by Mr. Percivall, from the Journal des Vet' 

 erinaires du Midi. 



