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been well observed; and in Cytinus R. Brown has traced the pollen- 

 tubes through the tissue of the style, into the ovarium, "where they 

 follow the direction of the placentae, and become mixed with the 

 ovula." The female flowers of all possess an unmistakeable ovarium, 

 furnished with placentae, to which the ovules are attached, each by 

 its funiculus : and the seeds, so far as they have been examined, are 

 found to have an embryo. In all these particulars the rhizogens 

 evidently agree with flowering, and differ from flowerless plants : 

 while the amorphous, fungoid character of their organs of vegetation 

 as clearly evince their relationship with the Cellulares. 



It is more difficult to make out their aflSnity as regards Exogens or 

 Endogens. In this part of the inquiry their organs of vegetation 

 afford us no assistance, since these organs clearly point out their re- 

 lationship with another division of the Vegetable Kingdom. The 

 almost normal structure of some parts of their organs of reproduction, 

 however, indicate the quarter in which we must seek information. 

 The quaternary or quinary arrangement of the floral envelopes, in 

 the majority of species, accords with the law obtaining in Exogens. 

 The condition of the embryo is a particular not so easily investigated, 

 and from the minuteness of that organ, as well, perhaps, as from its 

 not being in a sufficiently advanced stage of development when exa- 

 mined, it is diflficult to decide whether it be divided or not. Bauer 

 and Brown seem to be of opinion that the embryo is undivided ; but 

 Lindley, in speaking of the seed of Cynomoriura coccineum, says, 

 " On one side of this seed is a globular embryo, looking like a speck, 

 but found, when properly examined, to be a globose mass of cells, 

 destitute of starch, inclosed within the albumen, and apparently un- 

 divided on any part of its surface. It is, however, difficult to speak 

 positively upon this point, on account of its smallness, and / am not 

 sure that it is not very sligJitly 2-lobed.''^ But after all, the division 

 or non-division of the embryo, though in the more highly developed 

 plants of very great value, as indicative of accompanying peculiari- 

 ties of structure, in many of the humbler members of the Vegetable 

 Kingdom seems really to be of minor importance, since in some 

 avowedly exogenous genera, as the Monotropaceae, the embryo is 

 undivided, while some as undoubtedly endogenous plants possess a 

 divided embryo; and R. Brown says "an embryo of exactly the 

 same kind [as that of Rafflesiaceae and Balanoj^horeae] exists in Oro- 

 banche, and other, perhaps all other, genera parasitic on roots." 

 Indeed, when true leaves arc altogether absent, or are so deficient 

 in develo]>ment as they are in such plants as Rafflesiaceae, Oro- 



