1885.] Entomology. 1221 
completely in Eristalis, Bombyx and the Crustacea. In Eristalis the 
peri-opticon is traversed by a number of delicate tracheal vessels. 
The terminal optic anastomosis of Nepa is more complicated 
than it is in Periplaneta, and seems to be an intermediate stage 
between the simple anastomosis, the true peri-opticon of Musca. 
A similar series of intermediate stages between the simple 
anastomosis and a true peri-opticon has been traced in the devel- 
opment of these parts in the bee. 
The development and comparative anatomy of the peri-opticon 
of insects is interesting, as it may indicate the mode in which 
central ganglia were first formed from primitive nerve-fibrils and 
cells. : 
His investigations seem to him to corroborate the opinion of 
the majority of previous investigators, that the retinule are the 
true nerve-end cells. 
How INSECTS ADHERE TO FLAT VERTICAL SuRFACES.—Herr 
H. Dewitz gives an account of some further observations on this 
subject, tending to prove that the secretion by which, e. g., flies 
adhere to window panes, is not a thin fluid of a fatty nature, but 
much more consistent. He adduces experiments to controvert 
Rombout’s view that a fly can maintain itself on a glass surface 
by one leg only, if that surface be vertical and if the body of the 
fly be in contact with the glass—/ournal Royal Microscopical So- 
ciety, October, 1885. 
is stated by Dr. F. Dahl to occur in spiders. In an earlier com- 
munication this author had pointed out the fact that Micrommeta 
virescens and M. ornata were simply two broods of the same 
species. He now advances another instance in Meta segmentata 
and M. menger, stating his reasons for believing them to be respec- 
tively spring and summer broods of the same species.—/ournal 
Royal Microscopical Society, October, 1885. 
Entomotocicat News.—In the twenty-eighth volume of the 
Annales de la Société Entomologique de Belgique, we notice de- 
scriptions of the metamorphosis of Leptinotarsa d lineata Stál 
and Tropisternus lateralis Fabr., by Dr. Eug. Dugès of Mexico. In 
the first part of Vol. xxıx of the same Annales C. Van den Branden 
publishes a catalogue of the aquatic carnivorous beetles. The 
family Dytiscidæ numbered, according to the Munich catalogue, 
893 species; to-day the present catalogue enumerates over 1500 
species. C. Kerremans also enumerates the Buprestidæ described 
since the publication of Gemminger and Harold’s catalogue. 
In the Comptes-rendus of the same Society Mr. S. H. Scudder shows 
that the Brachypyge carbonis, described by Dr. H. Woodward as 
