BERKELEY, ADDRESS AT NORWICH. 237 



should long since have been pointed out by Mr. Newport, in 

 the case of certain insect parasites. 



A circumstance, again, which constantly occurs in the 

 diseases of plants confirms the views of Mr. Herbert Spencer. 

 In diseased turnips, gi'apes, potatoes, &c., it is especially the 

 vascular tissue which is first gorged Avith the ulmates which 

 are so characteristic of disease. 



Monsieur Casimir de Candolle, in a clever memoir on the 

 morphology of leaves, has come to the conclusion, after 

 studying the arrangement of their vascular tissue, that they 

 are branches in which the side towards the axis, Avhich he 

 calls the posterior, is atrophied. This subject has been 

 followed out in those organs which are considered as modi- 

 fications of leaves, as, for example, stamens, in which he 

 finds sometimes the posterior side, sometimes the anterior, 

 atrophied. If his theory is true, this would result from the 

 w'ay in which they originated, and the reference they bore to 

 contiguous organs. The subject iswell w^orth attention, and may 

 eventually throw considerable light on those anomalous cases 

 in teratology which will not accommodate themselves to the 

 usual theory of metamorphosis. Some of these cases are so 

 puzzling and complicated, that a very clever botanist once 

 told me, " Monstrous flowers teach us nothing," — not mean- 

 ing to abjure all assistance from them, but simply to indicate 

 that they may be deceptive. Such flowers as double prim- 

 roses, and the strange developments on the corollas of some 

 gloxinias, may possibly receive their explanation from a care- 

 ful study of the course of the vascular tissue. As the colour 

 on the anterior and posterior order in the latter case is 

 reversed, the doctrine of " dedoublement" does not at all 

 help us. 



Hofmeister,inhis ' Handbuchder Physiologischen Botanik,* 

 has an important chapter on free-cell formation, which at the 

 present moment is of great interest as connected with Mr. 

 Darwin's doctrine of Pangenesis. Mr. Rainey has shown 

 that the formation of false cells takes place in solutions of 

 gum and other substances ; and if this is the case where no 

 vital agency is concerned, we may well be prepared for the 

 formation of living cells in organizable lymjih, or in other 

 properly constituted matter. The curious cell-formation of 

 gum tragacanth may be an intermediate case. Be this, 

 however, as it may, Ave have examples of free-cell formation 

 in the formation of nuclei, in the embryos of plants, and 

 above all in the asci of ascomycetous fungi. In plants Avhose 

 cells contain nuclei ncAv cells are never formed Avithout the 



