187S. 



135 



It is most striking, that while the sexuated forms are deprived of rostrum in 



8cliizoneura lanigera, they possess that organ well developed in the closely allied 



,\h- Schizoneura comi, and also that this last insect has two winged forms in the course 



■ v'>' of its life, the emigrant and the pupiferous ; but ScJdz. lanigera has only the last form 



• ^ winged, and the emigrant, or second larval form, is apterous. 



Up to this day, I know the males and females in 14 species, viz. : — 

 With eostrum (Sexuata rostrata). 



1. — Schizoneura comi discovered by Leuckart 1858. 



2. — Vaccuna dryophila ... „ „ Huxley 1858. 



Without eostrum (Sexuata erostrata). 



3. — Phylloxera coccinea discovered by Balbiani 1874. 



4. — Pemphigus cornicularis „ „ Derbes 1872. 



5. — Phylloxera vastatrix ,, „ various persons ...1875. 



6. — „ quercus „ „ myself 1874. 



7- — „ acanthochermes. . „ „ „ 1875. 



8. — Pemphigus filaginis „ „ „ 1878. 



9.— „ Boyeri „ „ „ 1877. 



10.— „ ccerulescens „ „ „ 1877. 



11. — „ s][jirotheca3 „ ,, „ 1877. 



12. — Teiraneura ulmi ,, „ „ 1877. 



13. — Schizoneura lanigera „ „ ,, 1878. 



14. — Aploneuran.sp.? (lentisci?) „ „ „ 1878. 



I should feel very obliged by any information about the sexuated forms of the 

 following species, which are unknown to me, viz. : — Pemphiguslactucarius,vesicarius, 

 hursarius, coluteai,follicularius, semilunariiis, cornicularius,utricitlarius. Schizoneura 

 •ulmi, lanuginosa, veniista. Phylloxera corticalis. Vaccuna alni. 



By keeping winged lice in a glass tube, they generally give birth to their proves 

 in a few days. If the young ones look all alike, it is not the sexuated generation, but 

 if some are small and others about a fourth part larger, then it is surely the sexuated 

 period, and the winged insect is the pup i/erous form. — J. Lichtenstein, Montpellier: 

 llth September, 1878. 



Developed memhrane in British Pyrrhocoris. — In the valuable " British Hemip- 

 tera," p. 164, Messrs. Douglas and Scott, when describing the scarlet, black-spotted 

 Pyrrhocoris apterus, from South Devon, say : — " Membrane (in all British examples) 

 rudimentary; when developed, it has (according to Herrich-Schaffer, 'Wanz.,' ix, 

 173) two somewhat regular cells in the middle of the base, fi'om which eight irregular 

 forked nerves spring." It may, therefore, be not uninteresting to note that among 

 five examples of this species, sent to me from South Devon for naming, is one in 

 which the left elytron has a large and most perfectly developed membrane, not 

 truncate, but ovate at the apex. It is smoky-brown in colour, with the nerves some- 

 what darker ; at the base are four oblong cells, that nearest the front margin the 

 broadest ; the two middle cells have a small cell between their united apices, springing 

 from which, and from the broadest basal cell, three other cells are clearly to be traced ; 

 there are also indications of others; but the neuration becomes so evanescent towards 



