126 



CRUSTACEANS. 



hol, and examine the gills (which are beneath the abdomen 

 in this crustacean) and the mouth parts. Then remove 

 all the appendages of the body, arrange them in order 

 in glycerine upon a slide, cover with another slide, and 

 make a serial drawing of them as seen, magnified 10 to 

 25 diameters. Make a larger drawing of the terminal 

 segments of one of the first pair of thoracic legs, and 

 explain the action of these parts. 



THE CYCLOPS. 



Haunts and Habits. The water of an aquarium in 

 which aquatic plants have been growing is almost certain 

 to contain this animal. It is large 

 enough to be seen without a lens 

 (about a twenty-fifth of an inch long). 

 It appears as a white speck in the 

 water, is very active, and swims with 

 a peculiar jerky movement. Each 

 large female cyclops will usually carry 

 a pair of egg sacs attached at the sides 

 of the abdomen. 

 * 



External Features. Take up half 

 a dozen such specimens with a drop- 

 ping tube, place them in a watch glass 

 with water, and add a little ether. 

 Place them under the miscroscope, 

 and, having found one that presents a 

 good dorsal view, study it with low 

 power, to make out the following points as to its general 

 form : 



1. An oval body, tapering posteriorly. 



2. A dome-shaped carapace, covering the front of the 



CYCLOPS (X120). 



