1 1.9 
TWO CASES OF INTESTINAL MYIASIS 
By J. W. W. STEPHENS, M.D., Cantab., D.P.H. 
WALTER MYERS LECTURER IN TROPICAL MEDICINE, UNIVERSITY OF LIVERPOOL 
THE larvae to be described in this paper were procured from two young children 
in Liverpool, in October, 1903. In both cases the larvae were stated to 
have been passed per rectum. 
In the first case the larvae of two different species were present, viz., those of 
Musca corvina and Homalomyia canicularis. In the latter case the larvae of Homalomyia 
canicularis only. The latter larvae were brought alive to the laboratory, and an 
attempt was made to hatch them out by keeping them on a decomposing mass of 
faeces, flesh, etc., but as the larvae crawled out of this material on to the sides of the 
jar, they were subsequently, at the suggestion of Mr. Theobald, of the British 
Museum (Natural History), put in damp moss. They buried themselves in this. 
The jar containing them was covered with mosquito netting, and put in the hot 
incubator. About eight larvae were put in, and in about a month's time two flies 
had hatched out within a few days of one another. The flies were kindly identified 
by Mr. Theobald as H. canicularis, and the identification of the larva was thus 
established ; previously, Mr. Theobald had only been able to say that the larva 
belonged to the genus Homalomyia. As in the literature of this subject consulted by 
me the specific identification is rare, and as very few descriptions of the larvae are 
given, I have thought it well to describe the main distinctive features of the larvae. 
Larvae of M. Corvina. 
The larva varies in size from four to ten millimetres, is whitish in colour, 
thick, and bulbous at one extremity, tapering at the other end, and here a dark speck 
is seen with the naked eye, which under the microscope proves to be a single curved 
dark hook (Fig. 3).' The larva consists of eleven (?) segments, the head being retracted 
in the formalin specimens. On the head segment three antennae -like processes exist^ 
apparently consisting of three segments, but as these were retracted it was difficult to be 
certain about this. The most distinctive features are the lateral respiratory processes on 
the anterior end. They consist of eight processes on a somewhat thick column (Fig. 2). 
The ends of the processes are slightly bulbous, and appear to be really discs. The 
number eight distinguishes these larvae from those of M. domestica, which, according 
to Theobald, has seven only. 
I. The figures illustrating this paper have unfortunately been lost. 
