464 MAUD D. HAVILAND 
the proctodaeum is much enlarged with a bulb-shaped lumen, 
communicating with the exterior by the wide anus. In some 
examples newly removed from the host a transparent mem- 
branous substance was seen extruded from it. When larvae 
at this stage were stained with carmine or methylene blue, 
it was found that the stain readily entered through the anus, 
and was taken up by the lming epithelium of the hind-gut 
before any other part of the body was affected. 
TEXT-FIG. 7. TEXT-FIG. 8. 
Fig. 7.—Larva of the second instar. x 150. 
Fig. 8.—Intermediate stages of the larva. x 50. 
INTERMEDIATE StaGeEs (Text-fig. 8). 
As the larva increases in size the tail and cephalic papillae 
become reduced, and the thoracic processes disappear. It 
was not ascertained whether there was a moult between this 
and the previous stage, or whether the change of form was due 
merely to growth and absorption of the appendages ; but it 
is probable that there was at least one ecdysis about this time, 
though it was not actually observed. The body becomes much 
distended as the gut is filled with food matter, until the tail 
and processes finally vanish. After the disappearance of the 
cauda the anus gradually shifts back until it is at last terminal, 
and at the same time it becomes proportionately smaller. 
The egg, as previously mentioned, is usually deposited in 
