G. M. Thomson. — On the Fertilization of Floxvering Plants. 257 



described in Lubbock's work already quoted, and the former agrees well 

 with it in its fertilization. The outer anthers commence to open first while 

 the stigmas are still immatm-e and closely pressed together. But before the 

 pollen is all discharged the stigmatic surfaces expand, though they only 

 reach maturity after the anthers are emptied. 



Pelargonium I have not examined. 



Oxalis is represented by two common species, which differ very much in 

 their habitat, 0. magellanica being found in damp woods, and mountain 

 bogs and streams, while 0. comiculata affects dry, sunny localities. 0. 

 viagellanica has white scentless flowers. Of its ten stamens, five are long, 

 equalling the style in height, and five are considerably shorter. The an- 

 thers of the latter dehisce first, usually a couple of days before those of the 

 long stamens. The flowers when first open stand nearly erect, but the 

 peduncle gradually bends down, until by the time the petals are withering 

 they are completely pendulous. By this time the petals gradually cohere 

 together and close into a kind of cylinder, which in falling off smears the 

 stigmas with pollen. I was at first of opinion that the flowers were thus 

 self-fertilized, in the event of their not being crossed, but having cultivated 

 a large number of plants under glass, I found that all the flowers produced 

 were sterile, not a single capsule having set. 



The closely allied European wood-sorrel (0. acetosella) produces cleisto- 

 gamic flowers, but I have never found any on our New Zealand species. 



O. comiculata. The brilliant little yellow flowers of this species contain 

 a good deal of honey, and only display themselves on sunny days, which 

 makes me conclude that they are dependent on insects for fertilization, but 

 I have not been able to examine them minutely. 



Nat. Ord. Eutace^. 



Melicope simplex', the only representative of the order in Otago, is an 

 abundant shrub. Its flowers are more or less unisexual, the male having no 

 pistil, and the females having a full complement of stamens, but with 

 abortive anthers. The flowers have httle or no honey, but are sweet- 

 scented. They are not, however, individually conspicuous, nor are they 

 produced in large masses, and are therefore, I think, entirely dependent for 

 fertilization upon the numerous small Diptera which so commonly frequent 

 the edge of the bush. 



Nat. Ord. Olacine^. 



Pennantia corymbosa is entirely dependent on insects for fertilization. 

 The flowers are usually dioecious in function though hermaphrodite in struc- 

 ture ; but in the male flowers the ovary is only represented by a rudiment, 

 while in the female the anthers are abortive. They are pure white, produced 

 in great quantity, and are very fragrant; I have seen no honey. 



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