996 THE AMERICAN NATURALIST. (VoL. XXXV. 
existence in the presence of such forms in the large numbers 
that occur would be impossible. Its conspicuous color and 
slow movements render it easy of discovery and approach by 
those forms which use the sense of sight in finding their prey. 
Nevertheless the adult, the young, and the eggs appear to 
remain unharmed in most cases. 
I am inclined to believe that the abundant secretion of slime 
from the surface of the body and its increase under irritation 
renders Stichostemma more or less undesirable as an article of 
food. The slime is rather tenacious, and it is possible also that 
small animals are unable to pierce it and thus reach the body 
of the worm. 
The bodies of the worms when cut into pieces possess a 
slight but distinct fishy odor. As was determined by direct 
experiment, no decided taste is present. It may be, however, 
that the slime or the body possesses some quality which ren- 
ders it disagreeable to at least some animals; but even if this 
is not the case, the presence of the slime must afford a cer- 
tain amount of protection against attacks, at least against those 
of small animals. | 
In connection with the possibility that the slime may afford 
a means of protection, it is interesting to note that in the 
experiments with the cyprids the nemerteans became very 
quickly surrounded by the slime covering and remained enclosed 
in it until they were artificially removed the next day. In all 
probability the rapid formation of the slime “cysts” was the 
result of the incessant irritation of the surface of the worm by 
the cyprids crawling over it. As it formed and thickened, this 
slime furnished a covering which the cyprids could not pene- 
trate, or could penetrate only with difficulty after some time. 
SEXUAL RELATIONS. 
According to Montgomery, Stichostemma eilhardi is a pro- 
tandric hermaphrodite. Stichostemma asensoriatum is hermaph- 
roditic, but certainly not protandric. I have never found a 
purely male specimen of any size. The gonads are visible in 
the living animals, and the small odcytes can be seen very early 
