210 PROCEEDINGS OP THE AMERICAN ACADEMY. 



has been steadily gaining in probability since it was first announced by 

 Oken in 1 805, in " Die Zeugung," Frankfurt bei Wesche, 8vo.* This 

 work we have not yet seen, but in the first edition of the "Naturphilo- 

 sophie," Jena, 1809, II., XII. Buoh, Zoogeuie, he describes protoplasm 

 as ' Punctsubstauz ' and as giving rise to the ' Blasenform oder Zellform' 

 in both animals and plants. Oken considered the lower animals " Poly- 

 pen, Medusen, Beroen, kurz alle Gallertthiere," to be composed of 

 ' Punctsubstanz.' The nerves, the cartilage, and bones of higher animals 

 were considered as modifications of this form of ' protoplasm,' but the 

 skin and fleshy parts, including the viscera, were described as cellular, 

 " dem Fleisch liegt die Blaschenform zur Gruude"; again, on p. 30, "die 

 Eingeweide, welche am meistens aus Zellengeweb bestehen." Oken, in 

 XII., VIII. Buch, treats of the subject we are more immediately in- 

 terested with, and writes as follows : " Pflanzen und Thiere konnen nur . 

 Metamorphosen von Infusorien sein, . . . im kleinsten sind sie nur infu- 

 soriale Blaschen die durch verschiedene Combinationen sich verschiedene 

 Gestalten und zu hoheren Organismen aufwachsen," and also adds, on 

 p. 29, in anticipation of one of the points advanced by the author in his 

 " Larval Theory of the Origin of Cellular Tissues," f " auch besteht der 

 Samen aller Thiere aus Infusorien." 



This author directly compares his cystic or intestinal animals, In^ 

 fusoria, with ova, and speaks of them as oozoa, and in the preface to the 

 English edition of his Physiophilosophy, London, 1847, Ray Society, he 

 writes that all organic beings originate from and consist 'of vesicles or 

 cells. " Their production is nothing else than a regular agglomeration 

 of Infusoria ; not, of course, of species previously elaborated or perfect, hit of 

 mucoiis vesicles or points in general which first form themselves hj their 

 nnio7i or combination into particular species." Oken's view was based on 

 the resemblances existing between the Protozoa and the cells in the tissues 



* Through the kindness of Prof. George B.Tur I have received his copy of tliis 

 book, and find to my surprise tliat it contains quite different statements of Oken's 

 theory from that of the " Naturpliilosopliie." Tiiis autlior made great advances in 

 knowledge between 180-5 and 1809. In "Die Zeugung" he relies for the proof 

 tliat tlie more complex animals are descended from what we now call unicellular 

 organisms upon the constant presence of some of these in decaying flesh, assuming 

 that they are the disintegrated elements of the body itself and not independent 

 productions. 



He makes also, on p. 128, distinct statements asserting the parallelism of the 

 development of the individual to the evolution of the organic kingdom, but gives 

 only fanciful analyses in support of this position. 



t Proc. of the Bost. Soc. Nat. Hist., Vol. XXIII., March 5, 1884. 



