SOME AQUATIC WORMS, ETC. 183 



oblong white space in front of each. The mouth is near 

 the centre of the body, opening on the lower or ventral 

 surface. The worm glides smoothly and quite rapidly 

 over a submerged surface. Naturalists have named it 

 Plandria torva. 



The second one referred to somewhat resembles Pla- 

 ndria torva, but is usually smaller, and has the head end 

 more nearly triangular. It is similar in its movements 

 and in the presence of two black eyes near the front 

 border, each at the inner margin of a white space, thus 

 giving the \vorm a cross-eyed appearance. The body is 

 nearly white, and has a dark line passing lengthwise 

 through the centre and giving off on both sides many 

 short branches which are themselves often branched, 

 these dark lines on the white body giving the latter a 

 very pretty appearance. They are not for ornament, 

 however, but are the branching stomach. The mouth 

 is near the centre of the lower surface. The body may 

 measure half an inch in length. It has been named 

 Drendoco&lum Idcteum. 



The entire surface of both these worms is finely and 

 closely ciliated. The color of the body will at once in- 

 form the observer which one he has captured. 



IV..ANGUILLULA (Fig. 133) 



The body is thread-like, perfectly transparent and 

 colorless, about fifteen times as long as broad, rather 

 widest in the middle, whence it slightly tapers towards 

 both ends. The frontal border is rounded, but with a 



