66 
Another mode of progression is by means of their lentacpl®' 
This is perhaps the most rapid of all, but I have never 88® 
any of the animals voluntarily make use of it, except 111 
Lucernaricej I have placed them on the oral disc and tin y 
have travelled with ease and comparative rapidity by usifp. 
the tentacula, especially the Anthea, which is capable 0 
more variety of action than any of the others. They a ' 1 ^ 
said also to distend their bodies with water and allow tilt’* 1 ' 
selves to be washed abont by the random motions of tB 
sea ; this I have never seen. . 
This class of animals, so entirely destitute of solid p ar 
whereby they might perform their various muscular actio 0 * 
forcibly points out the resources of nature in overcocii'jr 
difliculties apparently insurmountable. Being so universal ) 
soft and gelatinous, no point, is offered as a fulcrum on wh ,L 
the muscles can act; but yet a great variety of definite actio* 1 " 
are performed with readiness, and are entirely under 1 ^ 
guidance of the animal. When they are about to ex e 
themselves, they imbibe water aud distend themselves to aB v 
vi 4< 4 T. - - _ . ] _ — _ I m 4 1 i ■ n .1 « . . 4 .. .v .1 .1 i v 4 n 4 a 4 I i ■ v . v ». ■ tl 4* PA 
In this distended state the orifice 9 
all other means of exit are closed, aB 
tli® 
extent they please 
the tentacula and 
thus, when the muscles act, they exert themselves on 
contained water, which, by resisting, becomes converted ,B 
a fulcrum as efiieaceous as it is simple. This mode of cp 
pensating for the want of solid points for muscular act 1 j 
is greatly diffused through the animal kingdom ; instances 
its exclusive use are to be found in the Physalia, or Portug 11 ^ 
man of war, where however, air is used instead of water; 
the feet of the Asteriadce, and in fact in all the Echiiioder» ia j’ 
and in a rudimentary state, in an organ of the highest ania 1 ® 
and in man. But this which is so rudimentary and n e3 ‘ r , 
disappears in the higher animals, is the sole means of eS ^ 
tion in many of the lower, and the mode of change is at ° B 
simple, effective and elegant. js 
The appetite of these, like most, of the rayed anim a ‘ s ’ e p 
of the most ravenous kind ; though they can, and have 
made to fast for twelve months, yet they are ready at J 
times for such food as chance or design may offer; she" 5 ^ 
the largest size, or the smallest insect are equally wulc° ^ 
The difficulties into which this great appetite freque® ■ 
throws them are of the most extraordinary kind. L)r. ■' B 9 ( 
ston mentions one of the Actinia Gemmacea ; the an* 
originally measured about two inches in diameter, ^ 
had contrived to swallow a shell ( Pecten maximns) 
size of an ordinary saucer. “The shell fixed with* 0 
stomach, was so placed as to divide it completely in 10 a g 
halves, so that the body, stretched tensely over, had be B ^ 
thin and flattened like a pancake. Ail communication bet'* 
