OF THE TRACHEAE IN INSECTS. 
157 
In Gryllus also and Forficula the mode of brandling lias much similarity to that of a 
tree; but in neither did I trace the fine tubules. In the larva of Acheta the termination 
of the tracheae, so far as it could be seen, resembled that of the perfect insect. 
In Melolontha, Scarabaus, and Lucanus I met with the same difficulty. In the larva 
of Lampyris and in that of Lucanus the distribution was much the same (PL II. lig. 6). 
In Necrophorus vespillo and N. humator the branchlets are long, waved, not very nu- 
merous, and without any special peculiarity in the mode of branching, which is generalh 
more or less dichotomous. The organ is provided with numerous white finger-like glands, 
on which the waved tubules had a beautiful appearance. Genenlly one or two run up 
each gland. 
The distribution of the tracheae in Libellula is very peculiar. Two large trachea 4 run 
along the stomach and give off about eight large transverse branches on each side in pairs. 
These lateral branches again give off branchlets at right angles, and these asrain others 
at acute angles. These last often run into one another, and thus divide the organ into 
numerous elongated compartments. 
In Fanorpa about ten large tracheae go to the stomach, on which they ramify in a 
radiating manner. There are also a few smaller systems, but by far the greatest number 
of tracheae originate from these large branches. 
The tracheae of Chrysopa and of Maynestra brassica (larva) resembled those of Tenth redo 
and Cynips, but I did not notice such long unbranched tubes. Sometimes the tracheae 
were here and there in tufts. Those of Compact margaritaria were still more like those 
of Tenthredo and Cynips, while Hipparchia again agreed with Chrysopa. 
In Musca and Eristalis the tracheae are in very pretty tufts. The ends of the tubules 
often run into the spaces occupied by other systems, but they very seldom inosculate. 
Sometimes the systems are more elongated, so as almost to lose the appearance of tufts. 
When magnified about 100 times, the tracheae have a beautiful appearance. 
In the larva of Musca the stomach is well supplied, principally by transverse branches, 
which, however, do not end in tufts. On the anterior part especially they are very 
pretty. 
In Tipula the tracheae are but very loosely attached to the stomach, so that they may 
easily be torn off in the dissection. They are not in tufts like those of Musca and Fris talis, 
but resemble those on the ilium. 
In Aphrophora spurn aria the tracheae are not very numerous, and consist of long 
waved branchlets, with few ramifications, much, in fact, like those of Lampyris and 
Necrophorus. 
In Fentatoma the stomach is complicated. PI. II. fig. 2 represents one of the tracheal 
branches magnified 60 times, and fig. 7 one of the lateral branchlets magnified 250 
times, of the anterior part. The branchlets divide dichotomously, and also throw out 
numerous tubules from the side. The tubules often run close together for some distance. 
On the posterior sacculated part of the stomach are thick, broad tracheae which send 
out large branches. These run principally between the sacculi, and appear to branch like 
those of the front part of the stomach. It is, however, difficult to follow them satis- 
factorily, on account of the folds. Pinally, there is a broader, short chamber, into which 
