PART I I 



CHAPTER I 



A.MCEBA — UNICELLULAR AND MULTICELLULAR ANIMALS. 



From your study of the frog you will have learnt some of 

 the more important facts with regard to the Morphology and 

 Physiology of a comparatively highly-organised animal, and 

 will have overcome a number of preliminary difficulties in 

 acquiring a knowledge of zoological terminology and 

 technique. \'ou will now, therefore, be in a better position 

 to undertake a systematic and comparative examination of 

 a number of other animals — some much less complicated, 

 some more complicated, than the frog — working upwards 

 from the simple to the complex forms and beginning with a 

 very instructive animalcule belonging to the genus AmcEha. 



Amoebas are often found in the slime at the bottom of 

 pools of stagnant water, adhering to weeds and other sub- 

 merged objects. They are mostly invisible to the naked 

 eye, rarely exceeding ]th of a millimetre (iJo''"' inch) in 

 diameter, so that it is necessary to examine them entirely by 

 the aid of the microscope. I'hough they can be seen and 

 recognised with the low power, the high power is necessary 

 for the accurate examination of their structure. 



