53 



have been seen to withdraw their pseudopoda and become 

 globular in form (Fig. 4), and finally the pseudopoda disappeared 

 altogether. (Fig. 6). In this state they remain for some time, 

 after which the tentacles or spines peculiar to the actinophrys 

 sol, are put forth. Fig. 13 shows them partly put forth. Fig. 9 

 shows them fully extended. In this form they are far more 

 formidable enemies to the colep hirtus than the amceba, and 

 indeed to every other animalcule in the cell, for if the colep 

 hirtus or other animalcule come in contact with the spines of the 

 actinophrys it is entangled by them and cannot escape, but is 

 gradually drawn into the surface. It is not wholly absorbed 

 into the body, but a transparent envelope is thrown round the 

 victim (Fig. 9, ff), by which it is held while the process of 

 assimilating the nutritious portions of the body goes on. This 

 is a peculiarity of these A. sols, which of themselves are very small 

 in comparison to what maybe seen laterof A. sol and A. eichhornia 

 which are large and are capable of taking into their bodies 

 animals of a greater size. These small ones only bring their 

 prey to the surface of the body by the agency of their spines. I 

 have seen three of the colep hirtus, each in a separate envelope, 

 attached to one A. sol (Fig. 9, ff.) The contractile vesicle is 

 seen at g. At times three or four actinophrys may be seen in 

 conjugation, and when thus combined are enabled to hold 

 several different animalcules as food. When full fed they again 

 separate, and gradually withdraw their spines, and each of them 

 divide in their centre into two kidney-shape bodies (Fig. 8). 

 From this form I could not trace them farther, so as to ascertain 

 what more changes might have taken place in their changeable 

 life-history. A number of amoebas, of the shape Fig. 17, were at 

 one time in the cell ; some of them had a great many more 

 pseudopoda than are represented in the sketch, and much less 

 in size, but e.xtended in length to more than twice the diameter 

 of the body, and gracefully bent in all directions, very beautiful 

 objects. Some of the amoebas after withdrawing their 

 pseudopoda and remaining stationary for some time (Fig. 10) 

 the centre becoming largely granulated, would again put forth 

 their pseudopoda and travel on, bearing the granulated mass 

 with them (Fig. 14). Some few of the amoeba took the form of 

 Fig. 11, the large and thick processes of which in the course of 

 an hour were seen to withdraw and assume the form of Fig. 12, 

 with the spines thickly set. They did not take on the form of 

 actinophrys sol, but continued to move on slowly in the 

 direction indicated by the arrow. This amoeba put forth spines 

 so very like to A. sol, that I think it most probable that it ulti- 

 mately resolved into that form. Fig. 7 is the amoeba bilimbcsa ; 

 Fig. 13 is the trachelocerca olor, showing the process of 

 longitudinal self-division ; this creature is shown in Prichard's 

 work on the Infusoria, and is described there by an observer as 

 having two heads, and named in consequence " trachelocerca 

 biceps," but this was evidently a mistake, and most likely was 



