114 MICROSCOPY FOR BEGINNERS. 



still water. They glide among aquatic plants and Algae, 

 especially on the lower surface of water-lily leaves, and 

 among Myriophyllum and Ceratoph} 7 llum. Sphagnum 

 moss is sure to contain them in abundance, as has al- 

 ready been stated on page 61. But the mud is an ac- 

 cessible and fruitful source of supply. To obtain them, 

 gently scrape with a big iron spoon or the edge of a tin 

 dipper the surface of the ooze from the mud in shal- 

 low ponds, and transfer it to the collecting-bottle. Let 

 the muddy mixture stand for a few minutes until the 

 Rhizopods settle towards the bottom, and carefully pour 

 off some of the water, adding more ooze if desired. 

 Pour the mud and water into saucers, and set them near 

 the window, when the Rhizopods will make their way 

 to the surface, and may be removed by the dipping- 

 tube. Do not place the saucers in the sunlight ; Rhiz- 

 opods prefer a little shade. They are invisible, conse- 

 quently the collector must collect on faith, as he must 

 usually do when out on a microscopical fishing tour. 

 But he will seldom be disappointed if he gathers the 

 surface ooze from the edges of somewhat shady ponds, 

 and avoids those places long exposed to the sun, and 

 never sinks the dipper into the thick black mud, which 

 contains no animal life of any kind. 



They are small and easily overlooked in the field of 

 the microscope, but when one of the unprotected forms 

 and a single shell-bearing Rhizopod is recognized, the 

 beginner will never again overlook any of them in the 

 material on his slide. The Amoeba will probably be 



