84 DOCTRINE OF CLEISTOGAMY. 
Dicranum Poems Web. & M. Wet rocks near the top of 
Powerscourt Wate 
dD. a ir serge Wiis In the wood on south side of Powerscourt 
an terf: 
Timmia a norvegica, Zett. Among crags on the west side of Lake 
ree Co. Wicklow. 
Orthotrichum gr Wils. On an alder tree at head of 
alttaaccdiney Gap ublin 
Hypnum Ne iene Brid., var. On wet spongy spots on the 
Sutton side of Howth. 
MR. DARWIN’S DOCTRINE OF CLEISTOGAMY. 
By 8. Le M. Moorz, F.L.S. 
Ar page 848 of his ‘Forms of Flowers’ Mr. Darwin argues 
with — to gegen that ‘‘if a plant were pr evented either 
early or late in the on from fully expanding its corolla, with 
some echettion in she a0 but with no loss of the power of self- 
fertilisation, then natural selection might = complete the work 
and render it strictly cleistogamic.” The examination of a very 
small female flower of a vegetable-marrow eee in the open air, 
has led me to dissent from this conclusion. 
his flower was ot two and a half times smaller than is usual 
with the species. All its parts were equally reduced ; the lobes of 
the calyx were a a unequal, as also those of the corolla, which 
was much paler in colour than is usual. here was nothing 
to remark about the styles and stigmas, except that the former were 
was greatly struck with the extremely small size of this 
flower, the difference between the two forms being much greater 
than in some undoubted cases of ae to opti aronaee by 
s the Hoya carnosa grou: ed by Mr. Darwin (I. c. p. 831), 
isch i was supposed to have been fertilised without floral expansion 
and production of stamens. But in a review of Mr. Darwin’s work 
(Journ. Bot. 1877, p. 376) I pointed out that there was only too 
much reason for the belief than an unfortunate blunder had been 
committed in this case. I may also remark that t there is no reason 
ordinary si e produced at the same time, but the plant was a 
healthy one "olgarad in the task of ripening marrows.* It was s the 
ne of these marrows came quite to perfection, and the cold weather of 
October sock ‘billed the plant, so that the small flowers were, I s suppose, due in 
great measure to the roe of the season. But this does not lessen the 
validity of the view here m 
