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 270 OBSERVATIONS ON THE NATURAL FAMILY

angular, and that in Corymbifera and Carduacece, or in all tubular florets, it is spherical or oval.

All the figures which this author has given of pollen in Cichoraceae represent it as a regular icosahedron, except that of Geropoyon glabrum, which is a dodecahedron. I believe neither' of these forms of pollen has been observed in any other family of plants.

A fourth remark on Composite I do not offer with abso- lute confidence, as it is opposed to the statement of M. Cassini, on whose general accuracy I have great reliance. It relates to the disposition of the branches of the style or stigmata, which according to M. Cassini are lateral, or right and left with relation to the axis of the common receptacle ; whereas, I consider them as anterior and pos- terior, though in many cases by a slight degree of twisting in the style they acquire what M. Cassini regards as their original position.

This may seem a point of very little consequence to establish. Independent however of the necessity of minute accuracy in every case, it appears to me to have some con- nexion with my fifth remark, which relates to the infernal 89] structure of the Ovarium of Composite. I am not aware of anything having been yet said on this subject further than that it contains a single erect ovulum, inserted at the base of the cavity. In addition to this, I observe in the greater part of Compositae, whose ovarium I have examined, two very slender filiform cords, which, originating from oppo- site points of the base of the ovulum, or of its short foot- stalk, run up, and are more or less connected with, the lateral parietes of the ovarium, until they unite at the top of its cavity, immediately under the style ; between which and the ovulum a connexion is thus formed. In many cases, as in Liatris sjjicata and Tussilayo odorata, these cords are easily separable from the ovarium, and have such a degree of tenacity that they may be extracted from it entire, along with the ovulum. In other cases they more firmly cohere with the sides of the cavity : and in those plants in which I have been unable to see them distinctly,

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