THE LOWER FORMS OF LIFE. 23 



one body, still having two nuclei, and a band of division. In the 

 next change, which is observed in Fig. 13, it will be remarked that 

 the dark spot shown in the centre of the nucleus (Fig. 12) has dis- 

 appeared, and that the contents in each division are now surrounded 

 by a delicate inner membranous envelope, separating them from the 

 outer cell wall, and also the two divisions from each other. In the 

 next (Fig. 14) the granular matter will be found to have formed 

 itself into a series of distinct round-looking bodies, which in Fig. 15 

 are seen to have subdivided into a much greater number, while an 

 outer membrane (d) now covers the cell. In Fig. 16 it will be 

 noticed that the inner envelope has become thickened and con- 

 tinuous all the way round, while the globular masses in Fig. 15 have 

 become changed into navicular or boat-shaped bodies. In Fig. 17 

 the band of division is finally withdrawn, and we now have a cell 

 full of the boat-shaped forms seen first in Fig. 16. These are the 

 larvse, which, when mature, are set free by the bursting of the cell 

 (Fig. 17), and become developed into the perfect Gregarince. 



Now let us notice the salient points in this beautiful series of 

 processes. We have, first, the union and mingling together of two 

 perfect gregarinids, then the formation of a cell wall, then that 

 marvellous division and multiplication of the nuclei, then the change 

 from the globular to the boat-shaped germs or larvae, the obliteration 

 of the division which separated the upper from, the lower part of the 

 cell, the liberation of the larvae and their development into beings, 

 lowly as they are, yet destined to occupy a place in the scale of 

 organised nature. And yet this creature can only be seen by the 

 aid of the microscope, and its home is in the intestines of worms and 

 insects ! 



It is most interesting, and well worth our while, to observe 

 attentively the changes which take place in these low forms of 

 animal life during their period of development. Not only do they 

 shadow forth much that is observed in higher forms of animal life, 

 but the changes themselves are very curious, and utterly incompre- 

 hensible to our limited faculties. Every movement and change 

 takes place with the most perfect order and regularity, and seems, 

 as Kolliker himself has remarked, to be under the direct operation 

 of the will of the creature. And yet how can we assign a will to a 

 speck of jelly containing a fluid and a few granules ? 



The division of the nucleus, when viewed under the microscope, is 

 a most beautiful sight, each particle into which it separates forming 

 the nucleus of a new growth (Fig. 14), which takes up all the 

 granular matter seen surrounding the nucleus in Fig. 13. These 

 new growths again subdivide, and the product is the more highly 

 organised bodies seen in Fig. 15. Observe, also, that in this stage 



