Page:Journal of botany, British and foreign, Volume 9 (1871).djvu/73

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expanding from above downwards; the perianth (a) consists of 6-7-9 distinct spatluilate segments, liooded at the top, imbricate in testivation, and marked by purplish spots; the stamens are equal in number to the perianth segments, and opposite to them; the filaments are erect, flat, ribbon-like, pale rose-coloured, ultimately pi'ojecting beyond the segments of the perianth, and attached to the back of the anther below the middle , the anthers are oblong obtuse, extrorse, yellow, 2-lobed, lobes obtnse, bursting at the sides by a terminal pore, which sometimes lengthens into a fissure. Pollen ellipttcal. The ovary is superior, sub-spheroidal, ob- scurely 3-lobed, 3-celled, with an axile placenta, disse|)iments sometimes complete, in other flowers partially deficient. Style terminal, longer than the ovary, and protruding beyond the perianth, conical, thick, fleshy, curved, purple, terminated by a three-rayed brownish pajjillose stigma. Ovules solitary in each cell of the ovary, kidney-shaped, attached to the placenta by a very short funiculus. On first opening the spathe it appears as if the upper part of the spadix were covered by stamen-bearing flowers and the lower part by female flowers, the styles of which are directed up- wards. In reality, all the flowers are hermaphrodite in structure, though not so in function; the stamens in the upper flowers (a) protrude and shed their pollen upon the upturned stigmas of the lower flowers (b), whose own stamens are still immature and enclosed within the perianth. Obviously this is a provision for a division of labour, as the pollen of the upper flowers impregnates the stigmas of the lower ones. These questions then arise: how, if at all, do the upper flowers get fertilized? and what pur- pose does the pollen of the lower flowers serve? The answers to these ques- tions are not at present forthcoming. In the accompanying plate (t. 113) for which w^e are indebted to Dr. ]\Iasters, the entire plant is shown much reduced in size; (a) is a flower from the upper part of the spadix; (b), from the lower part, with the style protruding; (c) is a vertical section through the ovary, showing the attachment of the ovules, (d) one of the terminal leaf-lobes with its perforation. — Gard. Chrou. 1870, p. 344, and fig. Iviii.

(To he continued).

��The concluding volume of the new edition of ' English Botany ' is, we are rejoiced to see, commenced. It will contain the whole of the British Grasses, and students of this difficult Order will doubtless find Dr. Boswell Syrae's excellent and elaborate descriptions of great assistance to them.

Dr. L. PfeifFer, of Cassel, has published a useful index to the vegetable kingdom, " Synonymia Botanica locupletissiraa Generum, Sectionura vel Subgeneruni ad fiuem auni 1858 promulgatorum." 12,908 genera are enumerated with their synonyms, and arranged according to End- licher's system; fossil plants are included. It would have been more use- ful had references to the books where the genus-names were first given, been appended to the name of their authors. A second volume will com- prehend an alphabetical index to the whole.

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