104 



S. HADWEN AND A. E. CAMERON. 



three-sixteenths of an inch wide and long enough to cover the lips of the horse. 

 The band is fastened by a buckle under the chin and attached to the head-stall by a. 

 similar buckle on each side and one on the front, as shown in figure 10. In order 

 to ehminate the possibility of the nose being unprotected when the strips fall away 

 too sharply as the animal raises its head, it is recommended that an extra leather- 

 flap, as figured, should be attached to the band directly over the nose and likewise 

 cut into strips on the lower margin. To secure a more rapid attachment of the 

 nose-band to the head-stall, spring-snaps might be used in place of straps and buckles. 



Fig. 10. Leather nose-fringe as it should be 

 adjusted on the horse's nose. Dotted lines 

 beneath the jaws indicate the outline of the 

 canvas flap, attached to the head-stall and 

 nose-fringe, for warding off the attack of 

 Oastrophilus nasalis. 



As a preventive measure against the attacks of 67. nasalis, a piece of canvas exten- 

 ding from the nose-band to the throat is attached under the jaws. It is riveted 

 to the posterior margin of the nose-band and fixed posteriorly to the ring of the head- 

 stall on each side by a stout cord. The inter-maxillary region is thus completely 



protected. 



Summary. 



The eggs of the three species of bot-flies discussed in this paper are distinguished, 

 by the fact of that of 67. haemorrhoidalis being the only one stalked. It is also longer 

 than those of the other two species, which are of about equal length. Further, it 

 is brownish black in colour, that of 67. intestinalis being whitish yellow and 67. nasalis- 

 yellow. The egg of 67. intestinalis adheres to the hair by clasping flanges, which 

 run only two-thirds of its length, whilst the flanges of the 67. nasalis egg run almost 

 the entire length. 



The egg of 67. haemorrhoidalis is not inserted nor screwed into the skin of the host. 

 The eggs of 67. intestinalis are laid indiscriminately on the body of the host, but pre- 

 ferably on the long hairs investing the inside of the foreleg. 67. nasalis lays its eggs 

 on the hairs of the intermaxillary space, and 67. haemorrhoidalis on the hairs of the 

 lips, preferably the lower. 



