270 INSECT AGENCY ON THE DISTRIBUTION OF PLANTS. 
It is probable that insects 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 
readily convey pollen from one plant to another, and, when the 
plants were different species, hybridization might be the result in 
a genus the species of which seem so liable to that phenomenon. 
Carduus Carolorum, which is supposed to be a hybrid between 
C. palustri is and C. heterophyllus, may have been produced by the- 
agency of Trichius fasciatus (a beetle belonging to the family 
Cetoniade), whose thorax and underside 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 found. 
he species of Meligethes (a genus of small beetles) inhabit 
flowers. M. Brisout, in Z? Abeille (vol. viii., January, 1872) points 
out the flowers in which the various species are generally to be 
found. Among these are Genista, Galium, Prunus spinosa, Sym- 
phytum officinale, Mercurialis p perennis, Tri ifolium medium, Solanum 
Dulcamara, Melilotus, Cyanoglossum officinale, Lotus and other Leg- 
uminose, Lamium album, Galeopsis, Mentha, Marrubium vulgare, 
Nepeta Cataria, Ballota nigra, Teucrium Scorodonia, Salvia, and 
other Labiate. Many species affect only one . kind of plant each, 
and in going from flower to flower cannot fail to carry pollen with 
them. Teucrium Scorodonia is a great favorite with many noc- 
turnal Lepidoptera, and this, perhaps, partly accounts for the great 
number of individuals of this plant. Moths usually abound in 
places where the Teucrium grows. 
Many flower-frequenting night moths have more or less strongly 
developed crests of hairs on the thorax. Many flowers frequented 
by these moths have blossoms with mouths directed to the horizon 
(i. e. neither drooping nor facing the zenith), and stamens more OF 
less exserted and ascending; styles also more or less exserted. 
When a moth visits such a flower it eithér hovers in front of it and 
plunges its haustellum into the corolla, or else rests on the flower 
and does the same. In either case it brushes the stamens with its _ 
thorax, and carries off unwittingly a supply of pollen to the next 
Z flower visited. Now, it is worth noting that some of the moths 
ce which hover (e. g. the Plusiide* and Cucullia) have very strongly 
ce * Have also crested heads. ee 
