Iti sects and Parasitic Diseases. 2^ 



domestica and Stomoxys calcitrans) dislod<red from adjacent walls, 

 in food and water containers proA'^ided for horses. 



In the summer months the fodder will be found to be frequented 

 by great numbers of flies of both species, Musca domestica pre- 

 dominating in both cases. That many of these are ingested can 

 scarcely be doubted. 



Johnston (1912, p. 76) records the occurrence of larvae of Habro- 

 nema muscae in Stomoxys calcitrans and Musca domestica in 

 Sydney, and in Musca domestica in Brisbane. If the parasite- 

 found by him in Stomoxys calcitrans was of the same species as 

 those found in Musca domestica, the occurrence of the former in 

 Stomoxys calcitrans would appear to be merely a rare accident, 

 inasmuch as on two occasions a massive infection of faeces was 

 supplied by me to both Musca domestica and Stomoxys calcitrans- 

 in the same jar, resulting in a heavy infection of the Musca 

 domestica and an entire absence o.f infection in the fifty Stomoxys 

 calcitrans examined. 



B. — Habronema microstoma (Schneider). 

 1.— Historical. 



In the adult stage Habronema microstoma has been known since 

 1866 as a i^arasite occurring in the stomach of the liorse, but 

 nothing has been known definitely of its life-history. 



Von Linstow (1875, pages 195-197) found in the heads of 

 Stomoxys calcitrans a nematode embryo and several larvae which 

 he, assuming them to be of the same species, described and figured 

 under the designation of Filaria stomoxeos. Noe (1913, p. 392) 

 states that Filaria stomoxeos of Linstow is identical with nematodes 

 found by him in Stomoxys, and considers LinstoAv's species to be 

 an intermediate stage of Filaria labiato-papillosa of cattle (see- 

 Ransom, 1913, p. 9). Ransom further remarks that Noe's state- 

 ments have been commonly accepted, but that it is impossible to* 

 judge definitely from the data given whether or not he (Noe) is 

 correct in his opinion as to the identity of the nematodes, and as 

 to their being intermediate stages of Filaria labiato-papillosa. 



From Linstow's description Ransom is inclined to consider 

 Filaria stomoxeos a species of Habronema rather tha.n a larval form- 

 of Filaria labiato-papillosa, and he suggests the possibility of it 

 being a larval stage of Habronema microstoma. 



Other than these suggestions nothing is available as to the life- 

 history of this form. 



