SOME COMMON OBJECTS 



59 



branched, feathery antennae, a compound eye, two 

 mandibles and jaws, and a big lower body in which 

 we can see the heart beating, and the digestive 

 apparatus. In a female specimen we may detect 

 eggs filhng a space towards the back. The Water- 

 Flea is really not a flea ; it is a crustacean, allied to 



-h. 



■ ov. 

 •b.c^ 



Fig. 20. — Female Water-Flea (Daphnia Pdlex). 



a', antennule ; a", antenna ; he, brood-chamber ; hr, brain ; e, eye ; 



/, furca ; gl . maxillary gland ; h, heart ; ov, ovary. 



the crab and the multitude of creatures of that 

 "ilk." There are several species. Fig. 20 repre- 

 sents Daphnia pulez, the Common Water-Flea. 



In the same haul we shall probably find another 

 crustacean of microscopic 'proportions — the Cyclops, 

 noted for its single eye in the centre of the head, and 



