38 THE JOURNAL OF BOTANY 



They extend right and left of the primary petiole. These so-called 

 " stipules " arise within the axil, and show no connection with 

 the leaf base, their vascular bundles being independent branches 

 of the cauline bundle which supplies a branch to the main leaf. 

 Finding that short branches frequently occur in the lower axils of 

 I), heteropliyUa, it struck me that the organs under discussion 

 might be the two lowest leaves of suppressed branches. They 

 seem, however, to arise from opposite sides of the same node, 

 whereas normal leaves are alternate. Diligent search has failed 

 to discover a branching D. macrantha : but I have found several 

 specimens of D. stricticaulis with short branches in the lower 

 axils. In these the two doubtful organs remain in their usual 

 position in the axil, and the branch bearing alternate leaves arises 

 between them. I think it most probable that they are axillary 

 leaves sui generis. Their function seems to be to increase the leaf 

 area. They can scarcely be related to the climbing habit of the 

 plant, because they are as well developed in the non-climbing 

 D. stricticaulis as in the climbing D. macrantha, and climbing 

 does not put any of the leaves of the latter out of use as assimi- 

 latory organs. 



Pollination I cannot adequately deal with at present ; a few 

 notes must suffice. I believe pollinophagous flies are the polli- 

 nators of both species. In 1910 I observed many hover-flies, of 

 the species which I saw visiting D. stricticaulis earlier in the 

 year, busily devouring the pollen of an undetermined Drosera* 

 whose pink flower looks much like that of the last named, though 

 its odour is different, more resembling that of D. macrantha. 

 After watching the flies I concluded that they were efficient polli- 

 nators. These flies visit many garden flowers in search of pollen. 

 Colour and odour seem matters of indifference, so there is reason 

 to believe that the flowers of both the species under consideration 

 would be freely visited should the fly be about. In our garden in 

 1910 the fly became more plentiful as the season advanced. This 

 seems significant, in view of the fact that D. stricticaulis pro- 

 duced a higher percentage of fruit than the earlier-flowering 

 I), macrantha. In this connection I have some interesting figures. 

 In the locality about two miles east of my home the flowers of 

 D. macrantha examined yielded 3-66 % of fruits (twenty plants, 

 five hundred and seventy-three flowers), and those of D. stricti- 

 caulis 26-95 % (fourteen plants, two hundred and thirty flowers). 

 In the locality three miles west of my home D. macrantha 

 produced 21-48 % of fruits (six plants, two hundred and forty-two 

 flowers), and D. stricticaulis 52-60 % (twenty-three plants, one 

 hundred and seventy-three flowers). Flowering commences in the 

 latter about a fortnight later than in the former place. These 

 facts seem to indicate that later flowering plants stand a better 

 chance of pollination ; but the relative importance of locality and 



* [A specimen of the plant referred to has been sent to the British Museum. 

 In the dry state it seems to differ little, if at all, from D. stricticaulis, but the 

 seeds are those of I), macrantha. It is probably a hybrid between the two 

 species.— S. M.J 



