70 
all depths to a little beyond low-water mark. The 
when expanded, resembles in form the naked Actiniae ; w ^ 
contracted it retires from sight into the calcareous cup. 
is to be found of all sizes from a mere speck to an inch 
height. In a very young state it is sometimes found p a ^ 
sitical on the Alcyonium digitatum, on shells, and the sta 
of sea weed ; but as these substances are very perjsbjm 
in their nature, and offer no solid foundation on wbic ^ 
stand, large specimens are never found on them ; op ro 
and stones, however, they are frequently large and in gr . 
profusion. In the youngest state the animal is naked, *' . 
measures about the fifteenth of an inch in diameter * , 
about the thirty-second of an inch in height. In the eari 
state in which I have seen the calcareous polypm 
there were four small rays, which were free or unc 
nected down to the base; in others I have notice^ i 
primary rays, but in every case they were unconnec 
with each other. Other rays soon make their appears 
between those first formed; They are mere calcare% 
specks at first but afterwards increase in size. I he ‘ t 
union of the rays is observed as a small calcareous riij 
the base of the polype, which afterwards increases both 
height and diameter with the age of the animal. » fll J 
In taking a review of the polypes of this order, we 1 . f 
that though there is a considerable resemblance in 
general anatomy to that of the Asteroid polypes; 
there is also a considerable advance in the complication * 
elaboration of their various parts. In both there is ^ 
radiate form of teutacula, the central membranous stonj^^ 
the intervening space between the stomach and sides o f 
polypes, the dividing the space by longitudinal septa, ^ 
one opening serving both for the reception of food and eje«‘ ( 
of the undigested remains. In this there are per«u a ® ]1 
organs set aside for the developement of ova, forming * 
defined ovaries ; the structure of the septa and the sid®jj 
the animal are of a muscular kind; and here also are 
to be the first traces of a nervous system ; all of which 
a considerable advancement on the two preceding ° rU j e j)t 
and their habits and intelligence also exhibit a correspo® 
elevation. 0 p1J 
The comparative smallness and simpleness of the 
calcareous species of our shores, has not allowed >j. t |,0 
observations to be made on the vitality or non-vitality 0 
polypidom. But few as they have been they greatly a ^ g ff 
the question. In young specimens the poly pidonis are^ _ s o 
small' and increase in size with the age of the poly P 
that the base of an old specimen is five, six and sonhy^iJi 
eight or nine limes larger than young ones. 
