ACTINIA. 251 
adhere to it, it is so like everything around, that it is very 
difficult to detect it,—so much so, that very often I have not 
had the slightest suspicion of an Actinia being at hand, till 
by some accidental pressure the water squirted up through 
its warts and tentacles. When the tide returns, however, 
the anemone unfolds itself in beauty, and a marine flower 
is immediately seen where there was nothing but sterility 
before. The tentacula are shorter than the body, and are 
annulated or variegated with white or red. 
17. Acrinia crassicornis. (Plate XIV. fig. 46.) 
Hab. On old shells and stones from deep water. 
This is a fine species, and one of the largest of our Actinie. 
It is larger than the last, less leathery, and more vividly 
coloured. Mr. Cocks says, that the most distinctive cha- 
racter is the readiness with which the rim of the peristoma- 
tious disc can be thrown into undulations, or twisted awry ; 
to which Dr. Johnston adds, the ease with which the body is 
filled with water until it becomes bladdery and diaphanous. 
He states, besides, that it never indues itself with an extra- 
neous covering, like the preceding. It is about four inches 
in height, and fully more when expanded betwixt the tips 
of the opposite tentacula. Its beauty will be very evident 
when we quote part of the description by Sir J. G. Dalyell 
