WESTON, ON THE ACTINOPHRYS SOL. 121 



1 soon became satisfied it was a natural phenomenon, for with 

 the same slow and steady motion by which all the food is 

 drawn in, and in the same manner as the connecting medium 

 of self-division, after separation, so were the l)urst cells drawn 

 towards the Actinoplwys, ultimately disappearing in its sub- 

 stance. I kept this creature under the microscope nearly the 

 whole day, and watched it constantly, feeding it as in all 

 other cases. 



Naturally expectant of a repetition of this proceeding, I 

 had soon the satisfaction of seeing it (for I had on some occa- 

 sions thirty or fortj- specimens in the cage at once), and have 

 watched the process as I have described upwards of a dozen 

 times. 



Does this emitted fluid contain the germ of future genera- 

 tions ? 



In BufFon's ' Histoire Naturelle ' he says that nature gives 

 to the Actinophrys Sol a mouth and an anus at opposite sides 

 of the body. These I have never seen, nor anything that 

 leads to a conclusion of their existing, for the food is admitted 

 into the body exactly at the base of the tentacle against which 

 it strikes ; so also are the excrementitious portions of the food 

 passed out at any spot where circumstances appear to force 

 them. This latter process I have frequently seen ; in one 

 specimen twice, in less than half an hour, at different spots. 



In watching the digestion of a Rotifer, it occurred to me to 

 see a dark body, composed apparently of the case, remain for 

 some hours in the same spot, and then gradually approach the 

 side, as if for expulsion, but while waiting for this to take 

 place, an opening in another part occurred, and excrement was 

 voided in quantity ; this voided matter lies amongst the base 

 of the tentacles, while the opening through which it has passed 

 closes, and then, with the same stealthy motion I have before 

 described, it is apparently driven along the tentacles (as if by 

 repulsion) beyond their extremities, finally disappearing in 

 the surrounding medium. 



I am aware that Pritchard gives the Actinophrys Sol " a flat, 

 pancake form," p. 554, but this I look on as an error. If the 

 cover of the cage in which the specimen is confined be gra- 

 dually and dexterously raised a little, with a 2-ord objective, 

 and No. 2 eye-piece, the animalcule may be made to take 

 a rolling motion, owing to the increased depth of water, 

 and its spherical form distinctly traced ; moreover, correct 

 focussing with the higher powers will give the very points of 

 the tentacles standing erect, which, by focussiny doivn, may be 

 traced to their bases, while, during the progress, the points 



