936 THE AMERICAN NATURALIST. [Vor. XXXV. 
the swallowing of the food, is probably due to the fact that the 
nemerteans are easily disturbed by a jar or movement of the 
dish containing them, and especially by the light. In such 
cases they probably release the prey or disgorge it, if partly 
swallowed, as in the case described above. 
There is no direct evidence that the adult animal takes other 
food under normal conditions. The fæces, so far as recogniz- 
able as such, always contained the setze of naids. Moreover, 
specimens have been kept for weeks in jars with many other 
animal forms, Protozoa, Turbellaria, rotifers, copepods, ostra- 
cods, etc., but no traces of any of these forms have ever been 
found in the alimentary canal. 
The nature of the food of the young individuals is a matter 
of interest. When first hatched they are less than a millimeter 
in length. Probably they do not take food immediately, but 
they certainly feed when from one to two millimeters in length. 
The food at this time probably does not consist of naids, for 
it is difficult to understand how these small animals could 
capture any except the very smallest. I am inclined to believe 
that they feed upon other small forms during these early stages, 
though I have no direct evidence upon this point. 
I have often suspected the animals of eating each other. 
In jars containing a large number of specimens there is always 
a remarkable decrease in numbers during the first weeks, and 
the walls and bottom of the jar do not show the whitish disin- 
tegrating masses that are always found, even after several days, 
in dishes where isolated specimens die. Moreover, it is the 
smaller animals that disappear, those remaining being of large 
size and appearing well fed. I think the circumstantial evi- 
dence in favor of the view that the worms readily devour 
members of their own species is very strong, but here again I 
have not been able to make actual observations. 
The animals are capable of living for a long time without 
food. Single specimens have been kept for more than three 
months in jars of clear water with no other life except prob- 
ably a very few Protozoa. In one case a jar containing à 
number of individuals was kept for six months. Three of 
the animals survived during this time. 
