258 . MICROSCOPY FOR BEGINNERS. 



length it is curiously lobed. The egg-sack of the fe- 

 male is short and small, and the attached end is length- 

 ened, somewhat like the neck of a bottle. The eggs are 

 very large, and about twelve in number. The body of 

 each sex is about two-thirds of an inch long. Chiro- 

 cephalus is often found in company with Branchipus, 

 usually in the spring, as early as the middle of March. 



17. BRANCHIPUS (Fig. 170). 



The flesh-colored or pale red body is stout and large, 

 often measuring an inch in length. The head is large, 

 and the frontal appendages of the male are long and 

 broad, as shown enlarged In Fig. 170. These hang down 

 on each ' side of the head, 

 and are formed of two quite 

 dissimilar parts. The upper 

 half is broad and thick, and 

 Fig. m-Branchipus about one- fifth of an inch 



(a male). 



long. It ends in a stiff, 



bristle-like prolongation of nearly equal length, with a 

 short, bristle-like tooth at the inner side at the point of 

 junction of the two parts. There are eleven pairs of 

 swimming feet, and the animal swims on the back. The 

 eyes are two, black, and elevated on the ends of short 

 stalks. The body of the female is as large and as stout 

 as that of the male. The egg-sack is noticeable near the 

 point of union between the posterior narrow portion of 

 the body and the broader front. 



It is a curious fact that Branchipus is killed by even 



