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at its base, — or, in other words, after the contact of the contents of 

 the sperm-cell and the germ-cell, — a new cell is to be seen within the 

 latter : we have thus two concentric cells, one enclosed within the 

 other. In the progress of growth, which at this early stage is pecu- 

 liarly rapid, a period arrives when the covering of the germinal vesicle 

 can no longer be distinguished : up to this period the exterior of the 

 two concentric globules is more deeply coloured with green than the 

 interior one, — a difference which disappears simultaneously with the 

 disappearance of their limits. The formation of cells now proceeds 

 at both extremities of the embryo, by what our author calls " bipolari- 

 zation." The embryo gradually assumes an elliptical form, its longest 

 diameter being placed transversely to the plane of the pro-embryo, 

 and of course comprising the axis of the future plant ; its anterior ex- 

 tremity being finally developed as the first gyrate frond, the analogue 

 of a plumule; and the posterior extremity or radicle tending towards 

 the ground. The formation of new cells now goes on at the tip in a 

 twofold manner : there is a feeble growth producing the stipes, and a 

 more vigorous growth destined eventually for the production of the 

 leafy portions of the frond. The author considers this elliptical em- 

 bryonic body the direct result of the contact above described, such 

 contact being a " true act of generation." The description of the 

 mode in which the first gyrate frond is developed, and the figures 

 which illustrate this part of the subject, are worthy of all praise : the 

 execution of the latter leaves nothing to be desired, unless it be the 

 confirmation of their accuracy by further observations. And here we 

 would remark that a contributor to the ' British and Foreign Medico- 

 Chirurgical Review' for October, 1849, speaks of finding Suminski's 

 delineations to be so completely borne out by personal observation, 

 in certain instances, that he gives the Count full credit for their ac- 

 curacy, even where the opportunity of testing them was wanting. 

 The paper in question is intituled ' Physiological Botany,' and dis- 

 plays an acquaintance with recent researches that is as creditable to 

 its author as it is uncommon in journals of a semi-scientific character. 

 After completing his observations on the ascending extremity of the 

 embryo, Suminski describes with considerable minuteness the forma- 

 tion of the root; but as this presents nothing remarkable or novel, we 

 purposely refrain from introducing it into an inquiry of which it con- 

 stitutes no essential element. The addition made by this learned au- 

 thor to our prior observations may be thus summed up : the discovery 

 of a female apparatus or pistillidium as distinct from the male appa- 



