BIGELOW: COAST WATER EXPLORATION OF 1913. 307 
none of the various species found are new to the Atlantic Coast or 
even rare, but when the location is taken into consideration and the 
effect of the conditions of such a location on at least two of the species, 
the collection proves to be of more than passing interest. 
It is not unusual to find fragments of hydroid colonies torn from their 
support or from the rest of the colonies, living for a considerable time 
as they float on the surface. The majority of the species in this col- 
lection are represented by just such fragments, but the fact that there 
are so many of these species must indicate that in this region a vortex 
must be formed by currents whose influence reach to the shallow water 
some distance away. Furthermore, it would seem that some time not 
so very long previous to the time of collection, there must have been 
a rather violent storm, sufficient to make the effect of the waves felt 
at a greater depth than usual, as some of the species represented are 
not usually found at low tide or even in very shallow water. It is 
doubtful if any data have been obtained as to the length of time that 
fragments or even whole colonies of hydroids would live under such 
conditions. It is quite true that Sargassum torn away by storms, 
will carry hydroids in a perfectly fresh condition for weeks, during 
‘which time they may be carried hundreds of miles by the current, 
but the case is scarcely parallel as the Sargassum itself remains in 
good condition during this period unless it drifts ashore and dries out 
in the sun. In the present instance, no support was present in any 
case except portions of blades of eelgrass. Even here if the roots were 
| attached, the eelgrass would remain fresh for some time, but there 
were no roots. There were only small fragments of leaves that may 
have been dead before they were carried away. In the majority of 
cases even this support was lacking, while one species, Clytva cylindrica, 
to which special attention is paid later, ordinarily making much use 
of a support, apparently regenerated and continued to grow without 
any support. 
Doubtless if the spot where these were found is a vortex, there 
would be abundance of food material and the hydranths would not 
suffer in that regard. They might be better off even than in their 
own habitat. If light and specific gravity have any special directive 
influence on the growth of the colony, some power must have been 
exerted to overcome it, since the different position of the support 
or the lack of it places the colonies in entirely new positions. Many 
| cases of adaptability to unusual circumstances have been cited among 
|hydroids and this must be added to the list. 
_ The thirteen species found make quite a varied collection, as only 
