BY T. HARVEY JOHNSTON AND M J. BANCROFT. 6S 



Soon after the appearance of Hill's work, Bull (1919) 

 published an important contribution to the study of 

 habronemiasis, in which he dealt briefly A\ith the larv8& 

 of the three species in the fly hosts just referred to, his 

 paper being* mainly concerned, however, with a study 

 of the granulomata found in horses and also of the nematode 

 associated with the condition. 



Contemporaneous Avork has then been in progress in 

 at least three Australian centres, viz., by Bull in Adelaide,- 

 Hill in Melbourne, and ourselves at Eidsvold, Queensland. 

 We have confined our study to the lar\^al stages and their 

 relation to domestic and native flies. Of these the most 

 important are the house fly, Musca dome-stica, and the two 

 flies which especially molest stock in Queensland, viz., 

 Muscxi vetvMissima Walker and Musca fergusoni Johnston 

 and Bancroft. The latter was previously known in 

 literature as M. australis Macquart, but we have lately 

 redescril^ed the insect as M. fergusoni, since the specific 

 name was preoccupied (Johnston and Bancroft. 1919). 



Ransom worked with one species of fly (J/, domestica) 

 and one species of Habronema. Both Bull and Hill employed 

 two species of flies {21. domestica and S. calcifrans), and 

 three of Habronema, but dealt almost entirely with 

 artificially -infected material. We have utilised nine 

 distinct species of flies — eight belonging to the Muscidae^ 

 and one to the Sarcophagi dae— and three of Habronema, 

 our work showing that no less than six Miiscids and one 

 Sarcophagid species can harbour both H. niusccB and 

 H. megastoma : that one Muscid (a blowfly) can become 

 infected with Habronema sp. indet. : and that the remaining 

 Muscid can become paravsitised by H. microstoma 



The characters of the larval worms have been so 

 carefully described and illustrated b}' Ransom and by Hill 

 that there is no need for repetition by us. 



