ENTOMOSTRACA AND PHYLLOPODA. 253 



red, brilliant purple, bluish with purple-tipped antennae, 

 whitish, or colorless. The animals may be found in 

 shallow pools in the fall and early spring, and occasion- 

 ally in slowly flowing streams. The external ovary is 

 single. 



11. CANTHOCAMPTUS (Fig. 166). 



After Cyclops and Daphnia this is the commonest 

 fresh-water Entomostracan in the writer's vicinity. A 

 gathering of aquatic plants can seldom be made in this 

 neighborhood without obtaining many of the graceful 

 little Canthocampti. They are visible to the unaided eye 

 as small, flesh-colored, or pinkish lines darting through 

 the water in short jerks, after the manner of most En- 

 tomostraca. Like all minute animals, they will collect 

 on the best lighted side of the bottle, where they may 

 be easily captured with the dipping-tube. The eye is 

 single. The antennae are short and quite hairy. The 

 body is long, narrow, and sub- 

 cylindrical, being widest and 

 thickest in front. There is no 

 distinct heart. The external Fig . 166 ._ Canthoc , mptus . 

 ovary is single. It is attached 



to the parent by the thinnest and apparently most deli- 

 cate part, although considerable force is necessary to 

 separate it from the body. The eggs are round and 

 opaque. The young differ greatly from their mature 

 aspect. Canthocamptus is found in almost any shallow 

 body of still water, and all the year through, even occa- 

 sionally in midwinter. It is shown in side view in the 



