164 DIMORPHISM IN ERANTHEMUM. 
abundantly fertile ones. The corollas of these are ab 
bular and tapering from an inflated base. ey are 
ultimately cast off unopened by the growing capsule. 
infertility of three of the commonest species in our gardens, D. macro- 
phyllus, D. nervosus and D. pulchellus,is very probably due to the absence 
of the small-sized flowers. 
— _ Ruellia tuberosa, L., is an interesting species which I add to the list of 
plants producing dimorphic flowers. The minute flowers of this species 
are recognized by Linnæus in his specific name R. clandestina, as also 
by Nees, who makes it the type of his genus Cryphiacanthus—a name 
again indicative to us of the dimorphic peculiarity, though he does not 
all from specimens raised from a single plant and grown under different 
conditions in this garden. In a cool, moist and shady border, it is an 
erect herb about 2 feet high, with elliptical-ovate, bluntish leaves, cuneate 
at the petioled base, wavy, and very nearly entire, from 4 to 5 inches 
long by 14 to 18 lines broad; on a dry and exposed site it is almost stem- 
less or prostrate, with small oblong-ovate leaves, tapering to the base 
and from 10 to 18 lines long. In both conditions the large fully deve- 
b 
which dehisce and complete fertilization before the fall of the corolla. 
The capsules of the closed flowers are from 10-13 lines long, and e 
regularly contain 18-94 seeds ; whereas we have seen those of ! 
8 
I have also detected closed and minute flowers on Dipteracanthws 
dejectus, D. patulus, and D. prostratus, and there are not a few other specie? 
of this genus indicated by Nees as producing minute flowers. 
however, as well as those previously enumerated, are probabl all pet 
seasonal conditions of a normal form, and are thus not even distingus 
able as Varieties, far less, as has 
W 
pi js voen hinted, of generic or specific valu 
characteristics. In the cold seaso 
pPPear. These have a funnel.shaped corolla an inch long, with a regt 
lar spreading 5-lobed limb of a bluish-violet colour. These are succes" 
in the hot season by minute, closed, and. perfectly self-fertile floweP? 
