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312 Miscellaneous . quills and tail deep brown ; bill yellow ; the feet lead-colour, and the membrane that borders the toes yellow. Total length, 20 inches ; bill, 2 inches and 2 lines ; wing, 10 inches ; tarsi, 1 inch and 10 lines. It differs from the typical Podica in having a portion of the lores naked, in the greater breadth of the tail-feathers, and in their being rather rigid. The only specimen I have seen, from which this description and the drawing have been made, was presented to the British Museum by the Right Hon. the Earl of Ellenborough. MISCELLANEOUS. On Polycotyledonous Embryos. By M. P. Duchartre. Since Jussieu, by a happy application of a principle first asserted by Ray, has taken the characters furnished by the embryo for the basis of the great divisions of the vegetable kingdom, all the ques-tions relating thereto have become highly important. The first of these characters is that deduced from the number of the cotyledons, according to which all embryonal plants have been divided into mo-nocotyledons and dicotyledons. This number is nearly always, in fact, one or two ; but according to the majority of botanists, it exceeds two in the embryo of a small number of plants to which the denomination of polycotyledonous has been applied. By a remark-able peculiarity these plants are distributed among several families and also genera of which the majority of species have the more fre-quently but two cotyledons ; whence it has been considered impossible to establish for them a special class. The object of this memoir is to examine if these plants are really provided with several distinct cotyledons, or have only two which are deeply divided into a variable number of lobes. I first show by several examples that the cotyledons, or the seminal leaves of the dicotyledonous plants, have a very marked tendency to divide on their median line, in various degrees, sometimes so deeply as to cause each cotyledonous lobe to be wrongly considered as constituting a distinct cotyledon. Amongst other facts, I have de-scribed and figured germinating plants of Dianthus chinensis, Linu., which show all the degrees of division from the slit of one of the seminal leaves to the complete division of each one of the two into two nearly independent lobes. I also show by a series of different states, that the embryo of the Macleya owes to a division of its cotyledons the remarkable appearance which has caused it to be de-scribed as possessing sometimes from three to four cotyledons. I nevertheless observe that, in some very rare cases, the binary whorl of cotyledons may become ternary ; of which examples are enume-rated. I then pass to those embryos the cotyledons of which are normally bipartite, and describe the development of that of Amsinkia and their germination. I show that the two cotyledons of these plants, sim-

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On polycotyledonous embryos

M P Duchartre
Annals And Magazine of Natural History (2) 3: 312-314 (1849)

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