OF CILIATED INFUSORIA 253 



specimens of these Rotifers mounted in the manner I have de- 

 scribed, in a damp chamber on the mantelpiece of my study. 

 Among them was found a young dead Macrobiotus, containing 

 two eggs. This microscope slip was examined every two or three 

 days, and a little more distilled water was added to that beneath 

 the cover-glass if it had begun to evaporate. The single Macro- 

 biotus existing in this drop of fluid was seen on March 22 to be 

 seemingly unaltered, but no photograph was taken as I was 

 specially watching other objects beneath the same cover- glass. 

 It was not again examined till March 25, when to my great 

 surprise I found within the integuments of the ' Sloth ' eight very 

 slowly-moving Ciliates, filled with red-brown corpuscles, together 

 with five pale, merely granular, spherical masses. Nothing of the 

 animal was left within the integument save the pharynx and the 

 suction bulb — not even the pigmentary lining : that had evidently 

 been swallowed by the Ciliates. The integument itself seemed 

 whole and entire, so that this astonishing transformation, which 

 had taken place within the space of three days, greatly piqued my 

 curiosity. 



Subsequently, therefore, I sought for specimens of Macrobiotus 

 containing eggs, in drops of the fluid and sediment mounted in 

 the way I have mentioned, and will now relate what was seen in 

 two other individuals. 



On April 20, a dead Macrobiotus containing four closely 

 approximate and rather irregularly shaped eggs was found in a 

 drop of the water and sediment just mounted for examination. 

 The specimen was not photographed at the time, but it was very 

 much like that shown in Fig. SS, A (x 115).' It was associated 

 with other organisms which I desired to keep under observation 

 for a time, so that the microscope slip containing it was placed, as 

 usual, in one of the before-mentioned damp chambers. On 

 April 24 I found the Macrobiotus in the altered condition shown in 

 B ( X 150). Its four eggs were no longer closely approximated, so 

 far as the first and second were concerned ; each of them had 

 become more or less completely spherical ; and there were now 

 distinct indications within of the formation of globules or vesicles, 

 such as were found in the Ciliates derived from the great red 

 Amoebas, and such as we shall find further on in a great Ciliate 



' This specimen was intended to have been photographed like others with 

 an enlargement of 150 diameters, but by mistake a wrong eye-piece was used— 

 hence its smaller size. 



