46 
remarkable that the regenerating power should otherwise be totally 
lacking in these animals. 
In the work quoted I have quite summarily recorded some 
observations and experiments on Bolina infundibulum, which prove 
that this species at least has, indeed, a quite extraordinary power 
of regeneration. . These experiments were made during a stay at the 
biological station at Trondhjem in the summer of 1911. It was 
my intention to carry these studies further, especially to make 
experiments also om the two other North Atlantic species, Pleuro- 
brachia pileus and Beroé cucumis. For that purpose I passed in 
tie summer of 1912 some time at the Little Belt, where Cteno- 
phores are generally abundant. That summer, however, not åa 
single specimen was met with. During a stay last summer (1913) 
at the Biological station at Plymouth I hoped then to get the 
material wanted for making such experiments — but again in valn. 
Though Pleurobrachia is otherwise common enough at Plymouth, 
only two small specimens were -obtained during the whole time I 
stayed there, from 10th June to 15th July. 
As I shall now not have-occasion to carry out such experiments 
for the next following years, I have thought it proper to publish 
this account of my experiments on Bolina infundibulum, in order 
to call the attention of experimental Zoologists to these animals, 
which appear to be' no less fit objects for studies on regeneration 
than their relatives the Planarians. 
For a long' time I had been suspecting that the genus Le- 
sueuria, which differs from Bolina alone in the lacking of the oral 
lobes, is nothing but specimens of Bolina which have lost the 
lobes”). It is, indeed, a well known fact, that these fragile animals 
are very easily damaged by rough sea. Though the suggestion lies 
1) A. G. Mayer (Op. cit. p. 20), after redeseribing Lesueuria hyboptera 
from the original description of A. Agassiz and having stated that 
it has never been seen since Agassiz found it in 1860, likewise says 
that he is "beginning to suspect that this so-called Lesueuria 15 
only a Bolinopsis infundibulum with its oral lobes torn off and the 
edges healed over to produce a rounded. contour.” 
