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 572 ON THE PLURALITY AND DEVELOPMENT

by a similar rudiment, and these lateral embryoniferous branches not unfrequently consist of a single vessel or cell, while the embryo of the trunk or principal branch is as generally derived from more than one.

That each of those opake bodies terminating the trunk and branches of the funiculi are really rudimentary embryos, is proved by tracing them from their absolutely simple state to that in which the divisions of the lower extremity be- come visible, and those again into the perfect cotyledons.

The results of this investigation in its present incom- plete state are, 1st, that the plurality of rudimentary embryos in Pinus (and probably in other Conifer a) is not only constant, but much greater than could well have been imagined independent of actual observation ; each impreg- nated ovulum not only containing several distinct funiculi, but each funiculus being capable of producing several embryos. In the ripe seed, however, it is a rare occur- rence to find more than one of these embryos perfected.

2ndly. That an embryo in Coniferce may originate in one or in more than one cell or vessel even in the same cord ; and it also appears that the lower extremity of the funiculus, the seat of the future embryo, is originally in no respect different from the rest of its substance.

The greater part of the appearances now described are represented in the accompanying Plate.

��372] April 20, 1844.

Postscript. — It is necessary to notice the recent publi- cation of a very important memoir by MM. de Mirbel and Spach on the development of the embryo in Coniferce}

These excellent observers confirm the principal state- ments of the preceding essay, with the brief abstract of which only they were acquainted.

They have also extended the investigation to Thuja and TaxuSy two genera which I had not examined, and in which, especially in the latter, the structure appears to be re-

^ Anuales des Sc. Nat. 2 serie, November 1843.

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