BY T. HARVEY JOHNSTON AND M. J. BANCROFT. 85 



which wc worked, M. fergusoni, is almost certainly identical 

 with M. australis Macquart {non Boisduval), a type locality 

 for which is the Solomon Inlands. It would be of interest 

 to know whether a similar condition is met with in Fijian 

 horses, as Fiji is another locality where, according to 

 Macquart, M. australis occurs. 



Patton and Cragg (1913, p. 345) mention that in 

 Madras, Musca nebulo is frequently infected with larvse 

 of an Oxyuris ( ? 0. curvula) from horses, these worms being 

 ingested while the fly is a larva. Infected flies are said 

 to soon die, being unable to feed owing to the proboscis 

 becoming rigid on account of the large number of mature 

 worms present. The short account suggests that the worms 

 are Habronema spp. H. muscce is known to occur in flies 

 in Bombay. 



We have not had an opportunity to test whether 

 M. fergusoni, or M. vetusiissima, can become infected with 

 Habronema microstoma. 



Stjmmary. 



1. Various flies, both native and introduced, are 

 capable of acting (in Queensland) as transmitters of one 

 or more of the three species of Habronema infesting the 

 stomach of horses. 



2. H. muscce and H. megastoma may Le transmitted 

 by the Muscids, Musca domestica, M. vetustissima, M. 

 fergusoni, M. terrce-regince, M. Jiilli, and Pseudojiyrellia 

 (cobalt blue sp.)— also by Sarcophaga misera ; no doubt 

 by other Sarcojyhaga spp. also. 



3. Anastellorhina augur can become infected with 

 Habronema ; probably other blow flies with similar habits 

 could also. They are not, apparently, normal transmitters 

 of the parasites. 



4. H. microstoma undergoes its larval development 

 in Stomoxys calcitrans and not in M. domestica. We have 

 not specially tested any of the other flies as possible 

 transmitters of the parasite. Lyperosia exigua is suggested 

 as an intermediate host for this species. 



5. Habronema spp. can make their escape from 

 infected flies into saliva. This is apparently the normal 

 mode. Thus horses become infected by larvse escaping 

 from parasitised flies settling on the mouth. 



