172 DESCRIPTION OF A NEW GENUS OF DIPTEROUS INSECTS, 



Collection of the Australian Museum; I have, however, lately found 

 a single specimen each of the pupa and imago labelled ^^ Batra- 

 chomyia ^-lineata ; in frogs of N.S.W.," in the collection of the 

 late Mr. W. S. Macleay. 



Between the months of June and December of last year Mr. J. 

 J. Fletcher obtained and kindly handed over to me three frogs 

 infested with Dipterous larvae which I have in all cases successfully 

 bred out ; I am therefore enabled to publish the characters of the 

 genus, and in addition to compare the few notes I have been able 

 to make with those of Mr. Krefft. 



As pointed out by Mr. KrefFt, the larvae are found between the 

 skin and flesh on difierent parts of the sides and back of the frogs ; 

 sometimes only one parasite is present, at others two or three, 

 whilst a spirit specimen of Helioporus cdbopttnctatus from W. 

 Australia, in the Macleay Museum, nursed as many as five. After 

 the emergence of the fly-larvse the frogs seemed little or none the 

 worse, though according to Mr. Krefft's statement they ought to 

 have succumVjed to the effects of the parasites. His frogs, however, 

 may have died of starvation. The presence of a full grown larva 

 is indicated by a glandular-looking swelling of the skin about half 

 an inch in length and having a small aperture at one end. Having 

 lived in their host for a certain at present unknown time, the 

 larvae leave their nidus and crawl away to some dark and damp 

 situation (such as the underside of a log or a stone*), become 

 quiescent; while their skin hardens gradually, blackens, and 

 becomes the puparium. The newly emerged larva is extremely 

 averse to the light, crawls very slowly, moving the anterior 

 portion of its body from side to side as if surveying the situation 

 or looking for some convenient spot in which to pupate. 



As all my larvae, except one, emerged and assumed the next stage 

 during the night, and as I was unwilling to sacrifice the only live 

 specimen which I had the brief opportunity of examining, besides 

 its being the only example reared from Pseud. Bibro7iii, I can 



* Last October, I found in a damp umbrageous spot on Saddle-back 

 Mountain, near Kiama^ a puparium attached to the underside of a leaf. 



