HS4i DB. MASTERS ON B^CHEA DIOSM^FOLIA. 



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Note ou the presence of Stamens within the Ovarium of BacJcea 

 diosmcefolia, Edge. By M. T. MASTiAis, Esq., M.D., F.L.S. 



[Eead AprU 5, 1866.] 

 [Plate VITl 



I OWE to the kindness of our President the opportunity of ex- 

 amining the flowers which form tte subject of the present com- 

 munication, and which afford an illustratiou of a very rare terato- 

 logical occurrence. 



In the normal flower there is a turbinate hollow calyx, whose 

 limb is divided into five serrated lobes ; alternating with these 

 latter, and springing from the throat of the calyx, are the petals. 

 Originating from the same annular disk as the petals are the 

 stamens, seven or eight in number. The ovary is partially adhe- 

 rent, surmounted by a style, with two or three loculi, and an axile 

 placenta, to which several small curved ovules are attached. 



The flowers upon which I have now to make a few remarks did 

 not present anything peculiar in their outer parts; it was the 

 ovaries alone which were the seat of the unusual appearances. 

 Partially immersed within the expanded top of the flower-stalk 

 and the calyx-tube, which is continuous with that organ, the ovary 

 with its style complete did not show externally any indication of 

 the change within. On cutting it across, however, in any direc- 

 tion, numerous perfect stamens (filaments and anthers) were seen 

 projecting from the walls of the cavity. In most of the flowers 

 that I examined, the ovary was unilocular ; but in a few there was 

 the usual axile placenta ; yet even in these latter cases the stamens 

 originated from the parietes of the cavity, and not from the pla- 

 centa. The stamens presented different degrees of development: in 

 some cases they were fully formed, the anther-lobes open, and the 

 pollen exposed ; while in other cases the filaments were involute 

 or circinate, just as the ordinary stamens are in the unexpanded 

 flower-bud. In some cases imperfect stamens were found, mere 

 barren filaments, with or without rudimentary anthers at the top. 

 In no instance did I find a perfect ovule, or, indeed, any trace oi 

 ovules. The stamens appeared to be arranged irregularly on the 

 walls of the ovarian cavity ; and while they were certainly more 

 numerous at the lower portion (that now generally considered to 

 be formed by the cup-like end of the pedicel), they were not want- 

 ing in the upper half of the ovary (or that which is probably 

 formed from the carpellary leaves). 



There has, however, been so much diversity of opinion as to the 



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