THE EQUINE HOSPITAL FORMULARY. 123 



CEstrus Equi. 



The hot, which is tlie larval form of the gadfly, is red, 

 and has eleven segments arranged in double rows. The 

 gadfly lays its eggs late in summer on the neck, shoulders, 

 and inner part of the fore-leg, especially about the knees, 

 and fixes them by means of a sticky secretion. The horse 

 licks these parts with the tongue, whence they gain access 

 to the stomach, where they fix on to the mucous membrane 

 by their hooks. When full-grown, they escape with the 

 fa3ces, and bury themselves in the soil, where they become 

 pupae, and then, after being in the earth about six or seven 

 weeks, they emerge from their cocoons as perfect dipterous 

 insects. '1 he bots live in the stomach during the winter 

 months, leave in spring or early summer, and remain in the 

 soil from June to September, and all perish in October. As 

 a rule they do not do much harm, but they may cause 

 rupture, perforation, or tetanus. 



Draught. 



Oil of turpentine, f. ^^i. 

 Linseed-oil, f. sxix. 



Draught. 



Glycerine of carbolic acid, f. 3ii- 

 Ether, f. ^ii. 

 Linseed-oil, f. ^vi. 



Draught (Cobbold). 



Sulphuric ether, f. 5ii. 

 Solution of carbonate of sodium, f. 5vi. 

 This draught is to be given to the horse when the 

 stomach is empty. 



