COLLECTING ANIMALCULES. 87 



contained in a phial or glass jar, as in fig. 51, having 

 observed where they are most numerous, either with the 

 naked eye, if they are large, or with a pocket-magnifier, if 

 they are small, either of the glass-tubes, having one end 

 previously closed by the thumb or fore-finger, wetted for 

 the purpose, is introduced into the phial in the manner 

 represented by the figure, this prevents the water from 

 entering the tube; and when the end is near to the object 

 which it is wished to obtain, the finger is to be quickly 

 removed and as quickly replaced. The moment the finger 

 is taken off, the atmospheric pressure will force the water, 

 and with it, in all probability, the desired objects, up the 

 tube. When the finger has been replaced, the tube con- 

 taining the fluid may be withdrawn from the phial ; and as 

 the tube is almost certain to contain much more fluid than 

 is requisite, the entire quantity must be dropped into a 

 watch-glass, which spreads it, and the insect may be again 

 caught by putting the tube over it, when a small quantity 

 of fluid is sure to run in by capillary attraction. This 

 small quantity is to be placed upon the tablet ; but should 

 there be still too much for the tablet, if it be touched with 

 the tube again, it will be diminished accordingly." If we 

 wish to place several individuals together on the tablet, it 

 is necessary that each should be taken up with the smallest 

 amount of water : to effect this, Mr. Varley suggests that 

 the tube should be emptied on a slip of glass, in separate 

 drops ; and with one of the capillary tubes, but just large 

 enough to catch them, they may be lifted out one by one, 

 and placed on the tablet. Generally speaking, it is neces- 

 sary to add a small quantity of vegetable matter to ani- 

 malcules, to keep them alive; and as many species are 

 found on confervas and duck-weed, some instrument is 

 required to take small portions of such plants out of the 



Fig. 52. 



jar in which they are growing. For this purpose Mr. 

 Varley uses the forceps fig. 52, made of brass ; the points 



