the Nitrogenous Matter of Plants. 117 



gamous plants and of some Characese, we extend it to Crypto- 

 gamia generally, both vascular and cellular, it will be found that 

 this vital act, whilst the subject of various metamorphoses, pre- 

 sents itself in individual organisms of determinate form, which 

 have for a long time been confounded, with Infusoria. 



The antherozoids of Chara, Nitella, of Ferns, Mosses, Equi- 

 setacse, Hepaticepe, &c, have been well studied, and described in 

 relation to their development, forms, and vital endowments, by 

 Thuret, Nageli, Suminski, Pringsheim, Derbes and Sober, and 

 others. Let us examine and discover whether the spontaneity of 

 movement with which these organisms are endowed be open to 

 question, and whether their origin in the metamorphosis or de- 

 velopment of the living proteine matters of the cells be still a 

 debatable point. For ourselves, we have examined them in 

 several Charon, in Nitella flexilis, in Marchantia polymorpha, &c; 

 and both the contractility and spontaneity of their movement 

 have appeared so decided that we have no hesitation in saying, 

 with all deference to those naturalists who deny them these pro- 

 perties, that their observations must have been made at inoppor- 

 tune seasons. 



The zoospores of Vaucheria clavata, mistaken by Nees von 

 Esenbeck for Infusoria, have been examined with respect to their 

 origin by Meyen, whilst Unger and Thuret have presented an 

 accurate history of their organization. Likewise the sporozoids 

 of different Fucacese have been studied by Decaisne and Thuret, 

 particularly by the latter observer, who has investigated with the 

 greatest care both their organization and their vital endowments, 

 in a large number of species. Now, on contemplating these loco- 

 motive organisms we shall perceive that, if the living nitrogenous 

 materials seen in movement within the cells of phanerogamous 

 plants have not the determinate form of Infusoria, like that of 

 the animalcular beings of antheridia and zoospores, there exists 

 nevertheless between the two the signs of a common parentage. 

 And it is a striking circumstance that the actually living and 

 moving zoospores proceed, so soon as fixed by one end, to 

 change their shape and to develope cells ; but although dead so 

 far as concerns our view, by reason of the screen which conceals 

 them from our research, still their substance carries on a latent 

 mode of life, and elaborates a plant which in course of time resus- 

 citates the motile organisms. Is not this circle of life sufficiently 

 remarkable to attract the highest attention of micrographers and 

 physiologists ? for does it not seem to reveal to us the true nature 

 of plants ? It is true that the differences between the Algse and 

 the immense majority of other plants are very wide ; still we 

 must not seek after the affinities between them in accessory 



