Pinks and Chickweed 7-5 
favour of self-fertilisation. And with that abandon- 
ment has gone the conspicuous petals, which have 
dwindled in size though still bearing evidences of 
their former glory. Thus in the genus Cerastium, or 
Mouse-ear Chickweeds, some species are cross- and 
some self- fertilised, yet all contain a disk of five 
honey - secreting glands, all have white flowers. 
Though five is the proper number of the flower-parts, 
as throughout the family, yet in the Erect Mouse-ear 
(C. quarternellum) they have been reduced to four, 
and the entire plant is smooth, whereas most of the 
other Mouse-ears are covered with hairs or down, 
often sticky, in order to discourage ants and other 
crawling flower-robbers. Now this Erect Mouse-ear 
does not care any longer if the ants do invade its 
flowers and kick the pollen from the anthers to the 
branched stigmas. It has therefore abandoned the 
hairiness still retained by its first cousins, it has 
become annual instead of perennial, and it has 
allowed its petals to become smaller than its sepals. 
“The Little Mouse-car (C. semidecandrum), that we 
find blossoming in early spring on every old wall, has 
petals not more than half the length of the sepals; 
and although the Broad-leaved Mouse-ear (C7. 
glomeratum) has kept its petals as large as its sepals, 
yet it frequently refuses to open its buds, and when 
this is done forcibly by the inquiring botanist he 
finds the anthers have discharged their pollen directly 
on the stigmas. This species has evidently determined 
to do without insects altogether in the near future, 
for sometimes it may be found to have no petals 
at all. 
The Field Mouse-car (C. arvense) is a perennial, 
8 
