PSYCHE. 35 
ary tubules. The gradual passage of the 
sulphindigotate could be traced through the 
excretory cells. The yellow and white 
forms of tubes are regarded as identical in 
function, and moreover the former are 
probably only a younger stage of the white 
tubes. 
The pseudoneuroptera are very like the 
orthoptera in the Malpighian vessels, and 
contract into the genuine neuroptera, when 
the number of tubes is only six or eight. 
Leaving the orthoptera, the other groups 
are then briefly treated. 
Dr. Schindler doubts Dr. Mark’s opin- 
ion that the vessels are ever solid in Le- 
canium, Aspidiotus, &c., as he has never 
failed to find a lumen in the case of every 
insect examined, although the genera-in 
question do not appear to have been among 
the number. 
The diptera are found to present sev- 
eral points of interest. The assertion that 
Culex and Psychoda have five Malpighian 
vessels is confirmed, and these genera are 
thus the only known exceptions among in- 
sects to the rule that the number of vessels 
istwo or some multiple. A singular differ- 
ence was found between Eristalis tenax 
and E. florens. The former shows the 
normal form of epithelial cells, while they 
are convex or even conical externally in 
the latter, giving the vessels a sort of 
gnarled surface, in the little hillocks of 
which the nucleus lies, drawing to it the 
granular contents of the cell, and leaving 
the inner portion pellucid. In Sarcophaga 
carnaria cells in different regions of a tube 
were seen multiplying by division and by 
proliferation. 
In the fan-winged moths six vessels were 
49 Giebel’s Zeitschr. ges. Naturwiss., v. 51, p. 493. 
found, as in other lepidoptera, contrary to 
Suckow’s affirmation that they have only 
four. In a noctuid pupa all six vessels 
were found opening into a simple duct, — 
probably a malformation. Important ob- 
servations on the sympathetic nerve supply 
of the Malpighian vessels was made in Lu- 
prepia, to which I can only refer. 
Dr. Schindler declares confidently that 
his researches must forever settle all dis- 
pute about the function of the Malpigh- 
ian vessels. They are certainly urinary 
organs. 
The opposite view is, nevertheless, main- 
tained by Dr. H. Simroth, in a paper on 
the digestive system of the larva of Osmo- 
derma eremita,® who believes that, in this 
ease at least, these vessels must be hepatic. 
First, because they open into the digestive 
tract on the same level with the posterior 
coecal appendages which exist in this 
larva, and the presence, moreover, of a 
gutter-like arrangement, which Simroth 
believes must lead their secretion even 
farther forward in the digestive tract. 
Second, he has not found urinary contents ; 
finally, because digestion must take place 
posteriorly to their insertion. We have 
such conclusive evidence in many cases of 
the renal nature of the Malpighian vessels 
that it is hard to believe that we have a 
real exception here; and if we concede to 
such an exception, the absence of renal 
organs must still be explained. Simroth’s 
arguments at least show the necessity of 
farther study of the action of the compli- 
cated parts in this insect, which Simroth 
carefully describes, but of which it would 
be hard to give an intelligible account here. 
Mr. Felix Plateau continues his re- 
