* 
242 Prof. J. C. Schiódte on the Morphology 
is removed. In the second place, a collision arises between the 
exigencies of the seventh pair of spiracle dines € modification 
of the last abdominal segment for the oses of generation, 
water, ma are cree odifind in various way die ac- 
Epia by special arrangements. In Nepæ the first two 
the seventh is prolonged into a pair o sabes e ex- 
tremely remarkable structure of the large spiracles, however, 
as well as of the two which are situated behind the prothorax 
and behind the metanotum respectively, has not yet been pro- 
perly orden aee and requires a new and thorough investi- 
on. e present occasion I shall only mention this 
essential fact, ‘whieh i is of importance for the following, that 
from the seventh pair (the respiratory tubes) two large trunks 
of trachez run through the whol lo length of the body*. In 
* Comp. Léon Dufour's celebrated and €— re 196 in 
‘Rech. Anat. et Physiol. sur les Hémipt.’; it gives a iod elementary 
view of the arrangement, but i is, " wi oa ar from 
servations, very inaccurate and incomplete as far as ces whe e E fore ce part is 18 
concerned, where the author has v rici it in aceordance 
assertion that the thorax is entirely without veg 
