108 r»K MicRoscorE. 



be almost completely separated. . . We find sarcode also in eggs, 

 in zoophytes, in worms, and in other animals; but then, as it 

 advances in age, it is susceptible of a more complex degree of 

 organization than in the lower scale of animals. . . . Sarcode 

 is without visible organs, and there appears no cellular structure ; 

 nevertlieless, it is organized, because it possesses the power of 

 extending parts of its body, of contracting and dilating : in a 

 word, it has life." 



By the observations of Dujardin a general interest was awak- 

 ened in the scientific world ; and especially among the scientists 

 of Germany. No doubt Dujardin's observations exerted a great 

 influence over subsequent researches. Observations were espe- 

 cially extended into the subkingdom of Protozoans, and as a 

 result we have the beautiful works of Meyen, of Max Schultze, 

 Williaipson, Ha^ckel and of many others cited in the I'ol3^thalmes 

 •of M. Schultze (1854); in the Foraminifera by Williamson .(1858), 

 .and the Radiolaria by Haeckel (1845). 



Thus tlie researches of the French scientist were ct)mfirmed 

 and extended, and the irritability of living inatter was especially 

 brought out. But in spite of the clear statements of Dujardin, 

 sarcode continued to be regarded as proper onl\' to inferior 

 beings, until in 1861 Schultze boldly affirms the identity of .sar- 

 •code with the animal cell in general, and now there remained 

 only to cross the Rubicon between the animal and tlie vegetable 

 •cell to unite the two kingdoms of Nature l)y a bond of union — 

 identity of i)rotoplasm in plants and animals. 



Whilst the zoologists investigated the jihysiological i»roperties 

 of protoplasni, the botanists did not remain idle. Already in 

 1772 Abb(' Bonavenatura Corti had observed intracellular circu- 

 lation, and later many other botanists observed various move- 

 ments in vegetable protoplasm, as may be seen from the writings 

 of HofmeLstcr, in his '• Treatise on the Cell ■' ( 1S()7). Since then, 

 this movement has been seen in Alga^ in fungi, and their plas- 

 modia, and soon the complete analogy of these movements with 

 those in sarcode was established. This conclusion was arived lit 

 tlirough the labors of Na^geli, Cohn, Thuret de Barry, Cienkowski, 

 Wigand, Pringsheim, Schacht, etc., and thus the way had lieen 

 prepared for the generalizing and tlie synthetic researches of 

 Brucke (1864), M. Schultze (1863), and W. Kuhnc (1864). who 

 ■demonstrated the complete identity of living matter in the two 



