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 PLANTS JAVANICiE RARIORES. 587

family having an undivided stigma ; unless in such cases the position of the confluent parts could be determined by that of the two vascular cords generally observable in the style, and continued into the axes of the lobes of a regu- larly bifid stigma, when belonging to an ovarium composed of two carpels. But even if this distinguishing character should be admitted to be general, it is certainly not with- out exception ; and in the only cases that I have examined in Gesneriacece, where the lateral position of the lobes of stigma may be supposed to exist, the apparent position arises from the extreme breadth and manifest division of the lips, the two vascular cords of the style being still anterior and posterior. 1

The only point of difference remaining, therefore, is cios the existence of albumen in Gesneriacece and its absence in Cyrtandracece. This character, however, is not absolutely constant, there being cases in Cyrtandracece where the [109 remains of albumen are visible in the apparently ripe seed ; and in several Gesneriacece it exists so sparingly as to be- come a character of very little value, 2 especially as it is not here connected with other more important differences.

1 Here follows a note " On the relative position of the Divisions of Stigma and Parietal Placentas in the Compound Ovarium of Plants," which, having been originally distributed also in a separate form, has been already given in vol. i. pp. 553— 563.— Edit.

2 The late Correa de Serra, in a very ingenious essay published in 1811, * endeavoured to establish a test for ascertaining the importance of albumen in relation to the affinities of plants, namely, that where the albumen is of a texture very different from that of the embryo, which does not absorb it in germination, its constancy may be depended on ; while in those cases where its texture is nearly similar to that of the embryo, which derives from it its earliest nourishment, its presence or absence becomes of little value. His hypothetical expression of this difference is, that in the latter case the embryo before germination converts part of a uniform substance into its own body, and in germinating derives nourishment from the remainder; in the former it selects what is suited for its nourishment, leaving a residuum which it does not afterwards act upon, and whose presence is therefore constant. Among the examples given of families in which this selection and residuum exist arc Graminete, Palmar, Nyctaginea, Caryophyllecu, and Euplwrbiacece.

Soon after the publication of this essay a paper was read before the Linnean Society of London, in which I endeavoured to prove that the test attempted to be established by Correa was liable to many exceptions, and that his liypo-

1 'Annates du Museum,' xviii. p. -206.

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