ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 321 



Apterygogenea from South Russia.* — Einar Wahlgren describes a 

 small collection of these insects made by Dr. E. Lonnberg in the 

 vicinity of the Caspian Sea, which includes a new species of Collembola. 

 Collembola have not hitherto been described from the Caspian area, and 

 the new species, named Entomobrya lonnbergi, shows some interesting 

 colour variations. Most of the specimens were white with black eye- 

 spots and a small black spot between the antennae. Others were elabo- 

 rately marked with black, the markings showing great constancy and 

 regularity. Between the two extremes a number of connecting links 

 exist, showing that the markings disappear in regular order. The other 

 species found have a very wide distribution. 



Structure of Collembola.f — M. Victor Willern has made a detailed 

 investigation of twenty-eight members of this little-known order. He 

 finds that, except in Smynthurus, the tracheal system is totally absent, 

 and that the head contains two pairs of metameric cephalic glands, 

 an archaic condition which recalls that seen in Myriopods. In the 

 Thysanura a single pair of glands only is present. In the Collembola, 

 as in Myriopoda, a post-antennary sense-organ is present, while in 

 Thysanura it is absent. The Collembola further differ from the Thy- 

 sanura in possessing no Malpighian tubules, the function of excretion 

 being carried on entirely by the fatty body which contains concretions 

 of sodium urate. In regard to the ovogenesis, the author has obtained 

 some novel results ; he finds that the ova are smaller than the nutritive 

 cells, and actually penetrate into these, so that previous observers have 

 mistaken follicular cells for ova, and ova for vitelline cells. According 

 to the author a similar error has been committed in the case of Cam- 

 podea. As to the relations of the Collembola, the author believes that 

 they constitute a phylum entirely distinct from the Thysanura, and of 

 more ancient origin. They are most nearly related to the Thysanura 

 Entotropha. The author adheres to the view that the Apterygota as a 

 whole are the most primitive of existing insects. The paper as yet is 

 published in hrief abstract only. 



South American Insects.^ — Filippo Silvestri briefly notes the occur- 

 rence of Projapyx stylifer O. F. Cook, previously only known from 

 Western Africa, in the Argentine Republic. As yet one specimen only 

 has been seen. In the same note the author describes a new member 

 of the Polyxenidas, as Synxenus orientalis g. et sp. n. The generic 

 definition is as follows: — Segmenta 2-11, praeter penicilla lateralia, 

 seriebus duabus squamaruin ornata. Segmentum ultimum conicum 

 apice setis longis partim arcuatis serratis radiatim dispositis instructum. 



Succession of Mouth-parts in Hydrophilus.§ — Herr P. Deegener 

 has studied a complete series of stages in the life-history of this beetle, 

 in order to test Fr. Meinert's conclusion that in insects with metamor- 

 phosis the succession of the mouth-parts is the very reverse of that 

 usually accepted. He finds that the order of succession stated by 

 Savigny — (1) mandibles, (2) first maxillae, (3) labium — is quite correct. 



* Ofversigt k. Vetensk. Akad. Forhandl., lvi. (1899) pp. S47-50 (3 figs.). 



t Bull. Acad. K. Belg., xii. (1899) pp. 760-7. 



1 Zool. Anzeig., xxiii. (1900) pp. 113-4. 



§ SB. Gee. Nat. Freunde Berliu, 1899, pp. 44-9 (3 figs.). 



June 20th, 1900 Z 



