8 CLASSIFICATION. 



remote in their structure and appearance from any 

 with which we are elsewhere familiar. Let the 

 reader cast his eye for a moment upon the annexed 

 engraving (Fig. 2), which represents a piece of duck- 

 weed gathered from a neighbouring pond, surrounded 



FlG. 2. MICROSCOPIC OCCUPANTS OF A LEAF OF DUCKWEED. 



Highly Magnified. 



1. Vorticella convallaria. 



2. Volvox globator. 



3. Vaginicola crystallina. 



4. Amphileptus fasciola. 



5. Navicula hippocampus. 



6. Amoeba diffluens. 

 1. Trachelocerca olor. 

 8. Polytoma uvella. 



9. Stentor polymorphus. 



10. Bursaria truncatella. 



11. Pandorina morum. 



12. Stylortychia mytilus. 



13. Paramecium aurelia. 



14. Euplotes truncatus. 



15. Euplotes striatus. 



by the microscopic creatures that live in its vicinity. 

 Some fixed upon the stem (Fig. 2, 9) like trumpets in 

 their shape, spread out their gaping mouths, around 

 which whirl the swarming atoms that they swallow ; 

 others, like wine-glasses in miniature, stretch out the 

 little bells that constitute their bodies, to the length 

 of their transparent stems in search of food, or if 

 alarmed, folding their stalks in spiral revolutions, 

 shrink timidly from danger (Fig. 2, i). 



The Volvox (Fig. 2, 2) silently revolves, a little 

 world within itself. Others (Fig. 2, e) of different 

 shape, resemble films of ever-changing cloud. Others, 



