SOME COMMON OBJECTS 53 



different varieties may be a valuable practical 

 acquirement. Starch is obtainable from most vege- 

 table substances, but the grains obtained from 

 wheat, rye, barley, oats, etc., are probably the 

 most common forms favoured by the microscopist. 

 If the worker possesses a polariscope (p. 40) he 

 should certainly examine property mounted starches 

 under polarized light. 



Probably the most fascinating line of study for 

 the beginner is the observation of the exceedingly 

 numerous minute life-forms, both vegetable and 

 animal, which are to be found in fresh-water ponds 



Fig. 18. — Net for Collection of Pond-Life. 



and salt-water rock-pools. To secure the requisite 

 material some collecting apparatus is needed, but 

 this need not be elaborate or expensive. Many a 

 time I have caught abundance of material with a 

 wide-mouthed glass jar which I attached to a string 

 and threw into a pond, drawing it quickly back to 

 me through the water, or allowing it to drag over the 

 mud. But a fine muslin net attached to a wire 

 ring, about 6 or 8 inches in diameter, fastened to 

 the end of a walking-stick, is more satisfactory, 

 particularly if the net is made to the shape of a cone 

 in the apex of which a small round bottle is fastened. 

 The bottle ought not to be too narrow in the mouth. 



