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the functions of ulterior developernent, for which it is more especially 

 destined. Among other things he states {Ann. des Sc. 4. 276. E.) that he 

 should not be surprised one day to find some Grass in which the midrib of 

 the lower palea actually became a new axis bearing other florets. I mention 

 this for the sake of remarking that such a case is known, without how- 

 ever admitting that it is any confirmation of M. Hawaii's views, which 

 are at direct variance with the laws of vegetable developernent, for 

 reasons which are so obvious, as to render it altogether unnecessary to 

 give them here. I have a monstrous Wheat, specimens of which I com- 

 municated in 1830 to M. Kunth and others, in which the midrib of the 

 lower palea actually becomes saccate towards the apex, bearing cm imperfect 

 floret, icith stamens, ovarium, and h]/pogynous scales, in its cavity. What 

 we know of the tendency to special developernent of buds in the margins of 

 leaves, and, from Ferns and the observations of M. Turpin, in the whole sub- 

 stance of certain monocotyledonous leaves, there is nothing in this fact to 

 excite surprise or to give rise to new theories ; but it is worth mentioning as 

 the only instance upon record of a flower-bud with sexual apparatus being- 

 developed under such circumstances. 



The embryo is here described in conformity with the views that are most 

 commonly taken of its nature ; that is to say, it is considered to consist of a 

 dilated lenticular cotyledon applied to the albumen on one side, and bearing 

 a naked plumula on the other side,- next the testa. It is proper, however, 

 to remark, that the opinion of the late M. Richard, that the part commonly 

 called cotyledon is a peculiar process, and that the plumula is a body con- 

 tained within the apparent plumula, has been lately adopted by Professor 

 Nees v. Esenbeck, in his Agrostologia Brasiliensis, but with some differ- 

 ence. Richard considered the cotyledon to be a part of the radicle, to 

 which he gave the name of macropodal, in consequence of its great supposed 

 enlargement in Grasses and some other families ; Nees v. Esenbeck, on the 

 contrary, seems to entertain the opinion that this cotyledon is a special organ, 

 for which he retains Richard's name of hypoblastus, although he does not 

 adopt the view that botanist took of its nature. But I think if we con- 

 sider the improbability of any special organ being provided for Grasses, 

 which is not found elsewhere, and if we consider how nearly alike are the 

 embryos of Grasses and certain Aroidese, in which the plumula lies within a 

 cleft of the cotyledon, it is impossible to doubt the identity of the hypo- 

 blastus of Richard and Nees v. Esenbeck, and the cotyledons of other Mono- 

 cotyledons. Indeed, the latter himself appears, in one place, to hesitate 

 about the accuracy of distinguishing them, when he says (p. 9), "Turn vero 

 hypoblastus pars qusedam habenda est cotyledoni analoga, magisque ad 

 interiora seminis quam ad externam corculi evolutionem spectans." 



The structure of the stem of Grasses is so much at variance, apparently, 

 with that of other Endogenous plants, as to have led Professor Agardh to re- 

 mark, that it is the least monocotyledonous of all Monocotyledonous plants. It 

 is probable, however, that its peculiarity does not depend so much ui)on any 

 specific deviation from the ordinary laws of growth in Endogena;, as upon a 

 separation of the parts at an early period of their growth. The stem of a 

 Grass, it must be remembered, exists in two difierent states, — that of the 

 rhizoma, and of the culm: the rhizonui, which is the true trunk; and the 

 culm, which may be considered ramifications of it. The rhizoma grows 

 slowly, and differs in no respect from the stem of other Monocotyledons, as 

 is evident in that of the Bamboo. The culm, on the contrary, which grows 

 with great rapidity, is fistular, with a compact impervious diaphragm at each 

 articulation ; a fact which must be familiar to every one who has examined 



