AMONG SIMPLE SAECODE OKGANISMS. 427 



endosarc. These are regarded by Haeckel as indicating a true mul- 

 ticellular structure, which he compares with the multicellular con- 

 tents of the central capsule in the Eadiolaria. He has further shown 

 that in the young state of various families of Eadiolaria, though 

 the central capsule is absent, the central part of the proto- 

 plasm-body includes a number of cells. He hence concludes that 

 the young Eadiolaria whose central capsule is as yet absent are 

 morphologically equivalent to Actinosphceria. It should be borne 

 in mind, however, that even though we adopt Haeckel's view of 

 the multicellularity of Actinosphcsria, the cells of this rhizopod 

 would be indicated solely by nuclei without any differentiated 

 territories of the surrounding protoplasm. 



Haeckel has made the very interesting discovery that the so- 

 called " yellow cells " of the Eadiolaria contain a substance which 

 cannot be distinguished from the starch of plants*. Acted on by 

 iodine the granular contents of these cells acquire an intense blue 

 colour. The quantity of starch which is thus contained in the 

 "yellow cells" of the Eadiolaria is very great. In some cases 

 more than half of the entire body of the Eadiolarian consists of 

 starch. 



Among the most interesting and important contributions to 

 our knowledge of the losvest sarcode organisms is Haeckel's 

 'Monograph of the Monera'f. Haeckel had already, in his 

 ' Generelle Morphologic,' grouped together under the name of 

 Monera certain organisms of the lowest conceivable kind. They 

 consist of an absolutely homogeneous and structureless mass of 

 sarcode, destitute in their fully developed and free-moving state 

 of external investing membrane and of internal nucleus and con- 

 tractile vacuole, and multiplying themselves by a self-division of 

 their substance. They are the simplest of all organisms ; indeed 

 it is impossible to conceive of a living being reduced to an ex- 

 pression more simple. 



JSTo character has yet been discovered in them which would 

 justify us in assigning them to the animal kingdom rather than to 

 the vegetable, or to the vegetable rather than to the animal : and 

 Haeckel unites them with the Ehizopoda, Flagellata, Diatomacese, 

 and some other organisms slightly higher than these, in order to 

 form an assemblage of low sarcodic forms which he regards as 

 neither plants nor animals, but as holding an intermediate posi- 



* Beitrage zur Plastidentheorie. 



t " Monogr. dei' Moneren," Jenais. Zeitschi*. 1868. 



