38 SCHMIDT ON THE COMPARATIVE PHYSIOLOGY 



General View, that " these FrustuU(S are beings having the 

 substance and the organic re- and decomposing forces of plants 

 ■with the locomotion of animals/' is satisfactorily proved. 



Are we, however, in the present state of our knowledge, justi- 

 fied in accurately defining the above line. of limitation between 

 animals and plants? Is it not high time to overthrow this 

 Chinese structure, as an obsolete descendant of systematic 

 scholasticism ; and to consider that from man to the primary 

 animal and vegetable cell, there exists no gap in the realization of 

 a general idea upon which nature as a whole is based ? 



In what does the spore of Vaucheria clavata'^, that simple cell 

 with its vibrating cilia which moves about for hours together in 

 water, differ from the young Medusa, the not less simple vesicle 

 which cleaves the waters of the North Sea with its ciliated bulbs ? 

 In what does the embryonic cell of the swimming Ascidia differ 

 from both of these? Do not all three, with the utmost pro- 

 bability, possess the same elementary form and composition? 

 The mantle of the Ascidia exhibits to us the substance and struc- 

 ture of the plant ; it must pre-exist essentially as such in the 

 ovum, for in the earliest stages of development of the latter, in 

 the earliest change of that indefinite chaos towards the future 

 organism, we find it already separated as a protective formation 

 to its contents (the bifurcation globules) f. It is highly pro- 

 bable that the transparent mantle of the Medusae possesses the 

 same elementary composition : hence the embryo of an Alga, as 

 regards its material substratum (form and composition), is iden- 

 tical with that of a Medusa or Ascidia; in the former, we have the 

 highest stage of development of the plant; in the latter, the 

 simplest form of the animal ! Cannot we apply the idea, so 

 important in its consequences, by which Steentrup J not long 

 since combined numerous observations, heretofore isolated and 

 apparently paradoxical, into an harmonious whole, in the same 

 manner to thr simplest forms of the animal world? I mean, 

 cannot we regard the Alga as the nurse of its more highly deve- 

 loped embryo ? The nurse of a Campanularia ^ exhibits no trace 

 of the phaenomena which we necessarily connect with the idea 



* Dv. F. Unger, The Plant at the Moment of its Animalization. Vienna, 

 1S43 (in Letters to Endlicher). \ 



f Milne-Edwards, /. c. I 



J J. J. Sm. Steentrup on the Alternation of Generation, translated for the 

 Ray Society, 1816. London. 



§ Steentrup in reference to Campanularia geniculata, p. 31, fig 52. 



