COLLECTING AT BAR HARBOR 41 
tal clearness, and as one gazes into it one object after another 
comes into view, until one is filled with astonishment at the num- 
ber of beautiful objects the pool contains. The little green balls, 
one half of an inch to one inch in diameter, which look like small 
green tomatoes scattered on the stones, are Leathesia difformis, an 
alga which cannot be mistaken for any other. Bunches of Corailina 
officinalis, which resembles coral, as the name indicates, are abun- 
dant. This alga should be examined with a magnifying-glass. 
It is covered with caleareous matter, and its peculiar form of 
growth is beautiful and interesting. 
The fronds of the laminarian Alaria esculenta are tiny here, 
while just outside the cave they are to be seen several feet in 
length, beating against the rocks in the swash of the waves. 
Thorny sea-urchins (Strongylocentrotus drobachiensis) make green 
spots which look like tufts of moss. Yellow and green sponges 
in little cones are spread over small surfaces. Starfishes and 
ophiurans are plentiful. The Purpura lapillus and Littorina litorea 
and rudis (periwinkles), so plentiful on this coast, are present. 
The Mytillus and the Saxicava and the Acmea testudinalis are also 
to be found. A green crab (Carcinus menas) is snugly hidden in 
a dark nook on the shady side of the pool, and many small crus- 
taceans scuttle away from under stones as they are lifted. The 
collector is always anxious for uncommon, or rather less plenti- 
ful, species, and here are found two specimens of nudibranchs, 
or naked mollusks, Aolis and Dendronotus. The Chiton ruber, a 
jointed mollusk, was also found here, and five species of sea- 
anemones were counted. As this is a favorite hunting-ground, 
the anemones have not been left to attain full growth; but there 
are very many small ones which at first are not distinguishable, as 
they retract their tentacles at the slightest disturbance of the water 
and are then quite inconspicuous. After a little time of quiet 
watching they will be seen putting out their tentacles and expand- 
ing their beautiful flower-like forms. It is useless to try to cap- 
ture them uninjured, so tightly do they adhere to the rocks, and 
the difficulty of preserving them in an expanded form is so great 
that amateur collectors had better leave them undisturbed to 
beautify the pool. 
