198 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 
ency to gather themselves into bundles, which, though they run in va- 
rious directions, have a common trend parallel to the ovarian tubes. 
The interspaces of the network are, for the most part, of an elongated, 
rounded form, their long axes being parallel with the general trend of 
the fibres. The majority of the nuclei are irregularly oval in shape, and 
contain numerous granules, which are darkly stained by hoematoxiline. 
Whether these nuclei belong to the fibrous tissue itself or to an endothe- 
lium covering it, I cannot say. The latter view seems tome more prob- 
able. 
A very singular modification of this tissue may be found in the tunica 
propria of the Malpighian vessels of Anabrus. Spiral bands wind round 
the tubes. These bands are composed of a network of fine fibres, with 
small meshes and occasional granular oval nuclei, each of which is sur. 
rounded by a little court (" hof ") of protoplasm. At first sight these 
bands might be taken for a nervous plexus, but closer examination re- 
veals their true character. In the locusts, as will be described shortly, 
there is a trachea which winds round each Malpighian tube in a spiral. 
It is possible that a similar disposition exists in Anabrus, though I have 
not observed it. In that case the spiral bands of connective tissue in 
the latter insect may be the means of fastening the trachea to the Avails 
of tlic Malpighian tube. 
The trabecular or retiform modification of the connective tissue is 
probably very generally, if not always, to be found in all invertebrates 
above the Gozlenterata. It does not seem to me necessary to give ex- 
tended references. I will, however, mention Grobben's figure. 206 
The nervous chain of Lepidoptera is covered in the abdomen, but not 
in the thorax, by a cord of connective tissue, originally described by 
Treviranus as a ventral vessel, "Baucbgefiiss." Its true nature was 
first recognized by Leydig in 1862, and more recently it has been the 
object of a special study by Dionys Burger, 267 who proposes for it the 
name of chorda supraspinalis. It is to be hoped that subsequent inves- 
tigators will search for this organ in the Orthoptera and other insects in 
which we may reasonably expect to find it. 
SEXUAL ORGANS. 
I. — Female organs. 
Ovary. — The ovary is composed of a number of separate tubes, each 
of which is more or less independent. They all have essentially the 
same structure histologically, the differences I have observed relating 
merely to the proportions of the parts to one another. Every ovarian 
tube begins in the thorax with a small cord (Fig. 04 ch.) of connective 
tissue, which, is said to be attached to the heart. 263 Graber states that in 
^Grobben: Die Geschicclitorgane Ton Squilla mantis. Sitzber. Wien Akad., Bd. lxxiv 1. Abth., 
p. 389. (Fig. 8 of plate.) 
267 Burger, Dionys : Uber das sogenannte Bauchgefiiss, etc. Niederl. Archir. fur Zoo]., iii ( 187G), p. 97. 
268 Leydig, Burmeister, Waldeyer, Lubbock, and others. 
