PARASITES OF SIMULIUM LARVAE 75 
GLUGEA MULTISPORA SP. NOV.: (Plate 4) 
Macroscopic appearance. In its later stages this parasite is 
present in the body cavity of its host as small rounded white 
masses often measuring as much as 1 mm. in diameter. There 
may be but one or many of these masses scattered irregularly 
throughout the whole body, which is not greatly swollen by 
their presence (pl. 9, fig. 1). Where there is only one it is not 
much larger than the more voluminous masses of a multiple 
infection, and since it does not then distort the body it is not 
very readily seen, especially as the skin of the host is not very 
transparent. 
Microscopic structure. If a small quantity of one of these 
masses be placed in a drop of water under a cover glass it is seen, 
under a high magnification, to consist of many more or less 
globular bodies, varying in size from 11.5p to 30u. The larger 
bodies consist of aggregates of numerous small sporoblasts or 
spores. By gently rolling the cover glass the latter aggregates 
can be readily broken up and will then be seen to consist of 
somewhat elongate spores measuring about 4u x 2.5u. 
Infe history. Sections of the parasitic masses stained with 
iron haematoxylin and orange-G show very beautifully the 
later developmental stages of this parasite, though, owing to the 
small quantity of material, [ have been unable to obtain as com- 
plete a series as I.could wish. Plate 4, figures 2 and 3, show the 
characteristic appearance of sections of the parasite in which 
the later developmental stages are sharply separated. 
Myzxosporidium. ‘The parasite at the time of discovery was in 
a rather advanced state of sporulation. Around the myxospor- — 
idium was a very definite membrane, though at this stage of 
development it was impossible to determine whether this was 
formed by the parasite or the host. The earliest stages were 
the sporonts, which occurred round the edges of the mass. 
Sporonts. These are rounded bodies measuring some 9p in 
diameter. The chromatic substance (fig. 4) is very diffuse and 
spreads in a network throughout the cell. I did not observe the 
primary division of the sporont, but it is evident that in later 
stages the nucleus assumes a more regular form at division, after 
