50 Annals Entomological Society of America [Vol. VII, 
Malpighian tubes are attached by a filament (Plate XIII, 
Fig.. 9-e) a short distance above the anal aperture. The 
proportionately large size of these tubules indicates that their 
function is not of ordinary or small proportions. They are 
made up of exceedingly large granular cells, with distinct 
nuclei, surrounding a thread-like lumen leading forward to 
the fusion of the two tubules, from which there is a connection 
into the tube leading into the rectum. These organs must 
be’ considered primarily as organs of excretion and capable of 
taking from the body cavity not only that material taken 
in with the food, but removing from the system the waste 
products of metabolism. 
Dr. Berlese declares that there is absolutely no continuous 
connection from mouth to intestine. However, the writer finds 
some sections in his series that show what can hardly be denied 
to be direct connections, (Plate XIII, Fig. 9-c). Berlese’s 
theory of digestion and assimilation is quite plausible and 
there is a good argument for its probability, for this connection, 
at best, is very small. The greater number of the sections 
that have been made—and I have sectioned several score 
of specimens—show the condition as Dr. Berlese describes. 
But it seemed possible that the result might be due to an 
imperfect technic, so that to find a united alimentary canal 
was the cause for cutting so much material. The results 
seem to point to this accomplishment. I think that it is in 
the killing that the trouble lies. We have to do with an insect 
with a rigid, chitinous exterior with the anal aperture and 
esophagus attached to chitin. The intermediate system pos- 
sesses two large bodies, the stomach and the Malpighian 
tubules, joined by a very delicate intestine, which, unable to 
withstand the sudden shock of certain killing fluids, is ruptured, 
with the natural result that many, if not most, of the insects, 
show a disconnected digestive system. 
This condition might possibly vary in the different Dias- 
pinine genera, yet this is not probable. More work is still 
to be done on the group as a whole, and should this finding 
be true it will be a point of morphological importance at least, 
though perhaps not altering the present accepted theory in 
regard to the manner in which this system carries on its digestive 
and secretive functions. 
