Mr. H.J. Carter on the Organization of Infusoria. 23 7 



had better be called ''granulation.^^ Gemmse grow out from the 

 surface, and do not appear to contain any portion of the nucleus 

 [ex, gr. Vorticellce)^ ; neither could I discover an elongated nu- 

 cleus, as Stein has figured, in the Amcehce and Acineta which 1 

 saw developing young Vo7iicellie, the former in plurality (one to 

 three), and the latter singly; if present in the amoebous form, it 

 was circular, and if in the Acineta, undistinguishable from the 

 general " granulation.^^ 



Again, — Where are these transformations to end ? Into what 

 kind of rhizopods do the sheathed Vorticellce pass ? How many 

 of the freshwater Rhizopoda are alternating forms of Vorticellce ? 

 How many actinophorous Ehizopods those of Euglence ? How 

 many more Infusoria pass into amoebous forms ? &c. are questions 

 originating in Stein's important discovery, which not only indi- 

 cate the necessity of further investigation, but a considerable 

 approaching change in the classification of Infusoria. 



It is desirable, also, that I should add here what little more 

 I have been able to collect respecting the development of the 

 Monads in the rhizopodous cell, which dwells and multiplies in 

 the protoplasm of the Characea3 f. This, it will be remembered, 

 I conjectured to be by segmentation of parts of the diaphane and 

 sarcode ; but before making any further observations on the sub- 

 ject here, I will again premise a brief description of this cell. It 

 is distinctly a Rhizopod, like Amoeba, or the sponge-cell, but of 

 greater tenuity, and without, so far as my observation extends, 

 a vesicula ; that is, I have not been able to recognize this organ 

 in it, though on dying it presents vacuoles. The nucleus, as 

 before stated, is clear at first, then becomes cloudy, and presents 

 one or more defined granules, afterwards semi-granular and 

 opake, and then uniformly granular throughout, when it appears 

 to multiply by fissiparation in the parent cell, and thus to give 

 rise to several daughter-cells, after the manner of a vegetable 

 cytoblast ; or to grow into an elongated granular body, of whose 

 ultimate development, while within the living internode of the 

 Characese, I am ignorant (fig. 93). But when the internode of 

 Nitella {ex. gr.) is about to die, and this rhizopod seizes upon 

 the green disks of the periphery and other nutritious matters 

 of the interior, now deprived of the vitality which kept them 

 together and thus exposed to the rapacity of the ascendant para- 

 site, the nucleus undergoes various changes, which arrests of 

 development at different stages, among the myriads which are 



* A similar process takes place in the roots of Chara, where the new 

 nuclei for the new buds come into existence in the protoplasm surrounding 

 the old nucleus, but at some little distance from it, after which the old 

 nucleus perishes. 



t Ann. and Mag. Nat. Hist. vols. xvi. p. 10, & xvii. p. 115. 



