138 



Habronema microstoma , which would probably be inoculated 

 by Stomoxys calcitrans. 



A granulomatous condition found commonly in the horse 

 and ass in various parts of the world, and known as "summer 

 sores," or "granular dermatitis," has the same etiology as the 

 granulomata observed in Southern Australia. 



Examinations have been made of a granuloma which 

 affects the region of the pastern of the horse in the Solomon 

 Islands, and it has been found to be a habronemic granuloma. 



Under the names "Leeches" in North America and 

 "Bursattee" in India are described granulomata affecting 

 equines. These granulomata possess characteristics that are 

 common to habronemic granulomata. No larvae have been 

 found in the tumours, and the etiology still remains somewhat 

 obscure. They possess, nevertheless, such a striking resem- 

 blance to habronemic granulomata that it seems probable that 

 they possess a similar etiology. 



G. Prophylaxis and Treatment. 



Prophylaxis should be in the direction of (1) ridding 

 horses of the adult forms of the genus Habronema which are 

 located in the stomach, and (2) in the destruction of horse 

 dung or its use in agriculture. Of these two methods the 

 second is more likely to bring success than the first, and in 

 time should accomplish what is aimed at in the first. 



Excision of the lesion will usually be found the best method 

 of treatment. Should the lesion be ulcerated and of such 

 a size as to be inoperable it is advisable to keep the surface 

 covered by some application -which will protect it against flies 

 and possible super-infection. The lesion may reduce in size 

 under this treatment and become amenable to surgical 

 treatment. 



Addendum. 

 Since this paper was submitted an opportunity has arisen 

 of examining the published record of the work performed by 

 Hill (1918), of which work reference has already been made. 

 In so far as they deal with the life-histories of Habronema 

 muscae, H. microstoma, and H. megastoma the present 

 writer's results, in the main, agree with and confirm those 

 obtained by Hill. Hill, however, concludes definitely that 

 Musca domestica "occasionally (possibly only accidentally) acts 

 as an intermediary" host of H. microstoma (p. 44). His 

 records of experiments 7 to 11, 13 and 14, where larvae of 

 Musca domestica were allowed to develop in sterilized faeces 

 to which larvae of H. microstoma had been added, show that 



