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 406 ON THE FEMALE FLOWER AND FRUIT OF

though ill several of the specimens examined they were greatly altered in a[)pearance, from a coating of mucous matter taken up and again deposited by the spirit in which the specimens were preserved.-^ A slight diflerence, indeed, seems to exist between the tissue of the apices of the styles and the other parts of their surface ; hardly sufficient, how- ever, to prove it to be stigma, tliongh this is no doubt the probal)le seat of that organ.

The next point of importance in the female flower o{ Raffle- 6'ia is the structure and gradual development of the ovula. These, in the earliest state observed, consist of merely conical or subcylindrical papillae, having a perfectly smooth surface as well as uniform internal substance.

The first perceptible change taking place in the papilla is a slight contraction at its summit, the upper minute con- tracted apex being the rudiment of the nucleus. Imme- diately below^ this contracted portion a dilatation is soon observable, which, gradually enlarging and becoming slightly hollowed, forms a cup in wdiich the nucleus, also propor- tionally increased in size, is partly immersed. This cup, the rudiment of the future integument, continues gradually to enlarge, until it completely covers and extends consider- ably beyond the nucleus, but without cohering with it. If a transverse section is made near the slightly depressed 2;26] apex of this integument, an extremely minute perforation or capillary channel, extending to the free apex of the in- cluded nucleus, may be observed.

This account of the gradual development of the ovuluni of Majjlesia, I believe, is in every essential point applicable to Phsenogamous plants generally, except that here one coat only is developed. It is, however, in some important points different from the description given by M. Mirbel, who con- siders the nucleus in its earliest state as included in the integuments, which in the next stage open and dilate so as to leave it entirely exposed ; they then, as he supposes, re- main quiescent until the nucleus has considerably enlarged.

��1 See Mr. Bauer's reprcbcnlatiou of the hairs iu this state, Tab. 22 (XXUI), ligs. o, 4, 5, 6, and 7.

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