OF THE FAMILY BACILLAKIA. 129 



investing membrane of the body, whereby the green matter was 

 often forcibly expelled from the shell at the transverse division ; it 

 instantly annihilated the motion of the molecules in the terminal 

 sacs, and the sacs themselves became so distended with fluid as to 

 burst and allow the molecules to escape. 



" The mode of reproduction was stated to take place, 1st, by spon- 

 taneous division ; 2d, by ova ; 3d, by interbudding, or the conjuga- 

 tion of two Closteria. 



" The author, after balancing the arguments of the two theories 

 respecting the classification of this body, gave as his reasons for re- 

 taining them on the side of the animal kingdom, the following sum- 

 mary : 



" 1st. That while Clostcrimn has a circulation of molecules greatly 

 resembling that of plants, it has also a. definite organ, unknown in 

 the vegetable world, in which the active molecules appear to enjoy 

 an independent motion, and the parietes of which appear capable of 

 contracting upon its contents. 



" 2d. That the green gelatinous body is contained in a membra- 

 nous envelope, which, while it is elastic, contracts also upon the 

 action of certain reagents, whose eflects cannot be considered purely 

 chemical. 



" 3d. The comparison of the supposed ova with cytoblasts and 

 cells of plants, precludes the possibility of our considering them as 

 the latter, while the appearance of a vitelline nucleus, transparent 

 but molecular fluid, a chorion or shell, determines them as animal 

 ova. It was shown to be impossible that these eggs had been de- 

 posited in the empty shell by other infusoria, or that they were the 

 produce of some entozoon. 



" 4th. That while it was impossible to determine whether the 

 vague motions of Closterium were voluntary or not, yet the idea the 

 author had formed of a suctorial apparatus, forbade his classing them 

 with plants. 



" Lastly, in no instance had the action of iodine produced its ordi- 

 nary effects upon starch or vegetable matter, by coloring it violet or 

 blue, although Meyen asserts it did in his trials. 



" The author therefore concluded that Closterium must still be re- 

 tained as an infusory animal, although it is more than doubtful whe- 

 ther it ought to rank with the polygastric families." 



