and its relation to that in the Animal Kingdom. 863 



represented as the introverted membrane of the embryo-sac, a ger- 

 minal vesicle which had remained unfecundated ; and in this, as well 

 as in the suspensor, the characteristic surface of attachment against 

 the internal wall of the embryo-sac. 



In the 'liotanische Zeitung,' 1856, p. 121 {Stachys sylvatica), the 

 same author publishes his latest researches. He has overlooked 

 the germinal vesicles in the vmfecundated embryo-sac. In the im- 

 pregnated sac he never found but one ; this he regarded as the pollen- 

 tube, which he supposed to have penetrated into the embryo-sac. 

 The point of attachment of the germinal vesicle to the embryo-sac 

 was looked upon by him as a hole made by the pollen-tube. 



Tulasne published first in the ' Comptes Rendus ' (1855, No. 12. 

 p. 790) a short report of the results of his later embryological 

 studies, which have since appeared in full (Ann. des Sc. nat. 4 ser. 

 iv. p. 65). So far as relates to the fecundated embryo-sac, they 

 agree perfectly with our observations, and especially contain many 

 proofs of the pecuUar circumstance that the end of the pollen-tube 

 often lies at a considerable distance from the point of attachment of 

 the fecundated germinal vesicle to the outside of the embryo-sac. 

 On the other hand, Tulasne in these cases, again, has been unable to 

 detect the germinal vesicles in the unfecundated embryo-sac. More- 

 over, we miss frequently in his figures, and indeed in all the very 

 recently fecundated embryo-sacs, any representation of the abortive 

 germinal vesicles or their remains. 



Tulasne' s (erroneous) view of the act of fecundiitiou has conse- 

 quently undergone no alteration. The fact that (at the end of his 

 essay) he considers it illogical to perceive the germinal vesicle in the 

 unfertilized embryo-sac, cannot alter the fact of our having seen it. 



A. Henfrey read before the Linnsean Society of London, March 4, 

 1856, a paper ' On the Development of the Ovule of Santalum album, 

 with some remarks on the Phseuomena of Impregnation in Plants 

 generally,' the essential contents of which are reported in the Annals 

 of Nat. Hist. ser. 2. xvii. p. 438 (published in Linn. Trans, vol. xxii. 

 p. 69). He thinks that Griffith was decidedly in error on the point 

 that the pollen-tube penetrated into the embryo-sac. The unfecun- 

 dated germinal vesicles detected in the embryo-sac are stated by him 

 to be devoid of a bounding cell-membrane, and he regards them as 

 mere masses of protoplasm (pre-existing protoplasmic globules). He 

 thinks that a similar relation is set up between the embryo-sac and 

 the end of the pollen-tube, to that existing in the conjugation of the 

 Alga. Soon after the pollen-tube has become adherent to the point 

 of the embryo-sac, the pre-existing protoplasmic globule — the ' germ- 

 globule ' — acqixires a cell-membrane and becomes an actual cell, the 

 germiyial vesicle, from which is produced the suspensor. 



I must abstain from any close discussion of Henfrey' s observations 

 until the entire memoir, with the drawings, is published, since I 

 cannot until then contrast and compare what I saw in the prepara- 

 tion kindly shown me by Prof. Henfrey, with his own views derived 

 from them. But I cannot help making a few remarks on the con- 

 clusions he has drawn. 



