12 THE INFLUENCE OF INSECT-AGENCY. 
perfects seed (as is said to be the case) is readily explained. The 
moth is rare in Britain, and I do not at present remember any 
record of its eis been seen visiting the flowers of “estar 
though it is generally taken in the act of hovering over flowers, 
notably Petunia id hon neysu ciokdes Though Sphinz Geavadiols occurs 
throughout Britain (even beyond the range of Convolvulus, e.g., 
Orkney), yet it is most especially a southern rea ny perhaps that 
may account @ some measure for the rarity in state (at least 
in my experience) of Convolvulus sepium in Scot a 
Dianthecia (a genus of night-flying moths) must exert a great in 
fluence upon the fertilisation (and consequent abundance) of Silene 
and Lychnis. In fact, the perpetuation of the race of these moths de- 
pends upon the fertilisation of the plants, since the larve feed only 
upon the unripe seeds. This is a case somewhat similar to, though 
by no means so extraordinary as, that mentioned by Professor Riley at 
the last meeting of the American Association for the Advancement of 
Science. Professor Riley showed how the fertilisation of Yucca de- 
ity 
plant, may have a supply of unripe seeds to feed upon. In regard to 
Lychnis and Silene, it is possible that if there were no Dianthecie 
the plants might be more numerous, since other moths visit the flowers, 
though the Dianthecie are the chief visitors. Silene maritima is the 
most frequented species (it is, perhaps, worth remarking ae it has 
also the largest flowers, and is, perhaps, the most numerou ee 
als—of course, in proport 
habitat); Lychnis F'los-cuculi is more especially visited by Denton 
Cucubali; and Silene Otites, aplantof theeastern counties, by Dianthecia 
ievabtienien: On the Continent this — frequents a veertie oe: 
culata. I know of no insect visitors tlene acaulis and Lychn 
alpestris. Possibly, if Lychnis Sondiott had more insect visitors, i it 
might be more abundant on our mountains, though the peculiarities 
of the locality (in ae at least) have doubtless something to do 
with its restricted ran 
It is probable that jsbite are the agents in the production of the 
numerous hybrids that occur between species of the genus Carduus, 
- on the flat horizontal top of whose heads various species of Lepidop- 
tera may often be seen. The downy bodies of these moths would 
—e convey pollen from one plant to another, and, when the plants 
e different species, hybridisation might be the result in a — 
the, species of which seem so liable to that phenomenon. Cardu 
Carolorum, which is cpl 4 to be a hybrid between C. palustris aii 
Cc. oral tes oh have been produced by the agency of TZrichius — 
fasciatus (a beetle belonging to the family Cetoniade), whose thorax 
and se a are very shaggy, and which loves to bury its head and 
shoulders in the head of a thistle. This beetle is rather rare in Britain, 
but is not uncommon in the district where Carduus Carolorum was 
d. 
The csigen of rn ay (a genus of small es inhabit flowers. 
M. Brisout, in L’ Abele (vol. viii., January, 1 pe points out 
flowers in which the various species are generally to be found. Amon 
