PHYSIOLOGICAL BOTANY. 



293 



podospermous and trophospermous. The free podosperm, 

 although very short, is the primary membrane of the 

 ovule ; after impregnation they become covered with 

 cells (otricelli), which arise from the growth of the sur- 

 rounding cellular tissue, and constitute the pulp, by 

 means of which the seeds become separated from one 

 another, and are lost in the pulp. The pulpy mass con- 

 taining the seeds is not connected to the receptacle or to 

 the summit of the flowering branch, but to the upper 

 part of the bark, where the petals, stamens, and the outer 

 styles arise, by means of a fibrous tissue which descends 

 so as to terminate in the seeds. This subject deserves 

 more minute examination, not only in regard to the 

 adhesion of the style to the ovary, but especially with 

 regard to Planchon's investigations, which appear to form 

 a supplement to those of Gasparrini. 



Note upon the Embryogeny of Taxm baccata. By MM. 

 DE MIRBEL and SPACH. Compt. rend., 1844, i, p. 114. 

 In addition to the embryo which is developed, the authors 

 found two vesicles ; they do not consider these as abortiv* 

 embryos, for long before the embryo appears, these vesicles 

 become adherent by their base to the apex of the embryo- 

 sac, and the tube (boyau), which is above each of them, 

 becomes elongated by means of the nucleus almost as far 

 as the surface of the upper end. Hence the authors con- 

 sider that they serve in impregnation. 



Investigations upon some Vegetable Monstrosities, which 

 may serve to illustrate the origin of the Pistil and of the 

 Nucleus. By AD. BROGNIART. Compt. rend., 1844, i, 

 p. 513. It is a question whether the seeds arise from 

 the axis, or from the margins of the carpellary leaves. 

 ' The example which it is my intention to make known," 

 says the author, " exhibits in its carpels all the stages of 

 the formation of the leaf ; it exhibits at its margin ovules, 

 some of which scarcely differ from the normal ovule; 

 others form imperceptible transitions to lateral lobes of 

 the carpellary leaf. If is taken from a plant of Delphi- 



