198 ON THE ASCLEPIADE.E.
under surface there is no appearance of a suture, or any indication of their having originally consisted of two distinct parts : along with them separate also the descending pro- cesses, which are compressed, membranous, and light brown ; their extremity, which is still unconnected, being more gelatinous but not perceptibly thickened. The pollen has acquired the yellow colour and the degree of consistence which it afterwards retains. On the bursting of the cells, the gelatinous extremity of each descending process becomes firmly united with the upper attenuated end of the corre- sponding mass of pollen. The parts are then in that con- dition in which they have been commonly examined, and are exhibited in the figures of Jacquin, who having seen i7] them only in this state, naturally considered these plants as truly gynandrous, regarding the masses of pollen as the antherae, originating in the glands of the stigma, and merely immersed in the open cells of the genuine antherse, which he calls antheriferous sacs ; an opinion in which he has been followed by Rottboell, Koellreuter, Cavanilles, Smith, and Desfontaines. The conclusion to be drawn from the ob- servations now detailed is sufficiently obvious • but it is necessary to remark, that these observations do not entirely apply to all the plants which I have referred to the Ascle- piadese, some of them, especially Periploca, having a granular pollen, applied in a very different manner to the glands of the stigma : they all, however, agree in having pollen co- alescing into masses, which are fixed or applied to processes of the stigma, in a determinate manner ; and this is, in fact, the essential character of the order. Dr. Smith, in the se- cond edition of his valuable " Introduction to Botany," has noticed my opinion on this subject ; but, probably from an indistinctness in the communication, which took place in conversation, has stated it in a manner somewhat different from what I intended to convey to him : for, according to his statement, the pollen is projected on the stigma. The term projection, however, seems to imply some degree of impetus, and at the same time presents the idea of some- thing indeterminate respecting the part to which the body is] so projected may be applied. But nothing can be more
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