PLATE II 



MICROPHOTOGRAPHS OF ROTIFERS 



Adineta, Hydatina,' Diaschiza 



FIGURE 5. Adineta grandis under the influence of Eucaine. The trunk and anterior 

 part of the body are of the normal form. The Eucaine has caused the foot to be 

 drawn in, which would not usually be the case in the natural condition. The two 

 examples, of which portions are seen at the foot of the photograph, show the 

 deep constrictions of the neck which are caused by the influence of the Eucaine 

 on the muscles of the trunk. 



FIGURE 6. A very large example of Adineta grandis. It is under slight pressure, 

 so that the foot could not be drawn in. The head and neck have been moved 

 while the photograph was being taken, but the central trunk shows clearly the 

 six contained young. 



FIGURE 7. Hydatina senta, side view. This is the only free-swimming Rotifer which 

 we obtained in the Antarctic. It appeared in Coast Lake in summer. The 

 photograph is taken from a living example, under the influence of Eucaine, which 

 causes the cilia to move very slowly. The natural shape was not affected by the 

 narcotic in this instance, though it frequently causes some distortion. 



FIGURE 8. A small Rotifer, probably Diaschiza tenuior, seen from the side. It was 

 narcotised, and was showing the natural form very well when the plate was put 

 in, but at the very moment of exposure the body has become turgid, which is an 

 indication that death is imminent. 



Close under the head of the Rotifer can be seen one of the small Diatoms which 

 are common in the lakes. 



