408 EVENINGS AT THE MICEOSCOPE. 



I am going to bring under yonr notice this evening 

 some highly curious examples of animal Aveapons, of 

 which the very existence was until latelj"- altogether 

 unsuspected ; yet so profusely distributed that they are 

 eminently characteristic of the two great classes of 

 animals we have been recently considering — viz., the 

 Medusse and the Zoophytes. They have repeatedly 

 fallen under our observation in examining the speci- 

 mens of these creatures which we had selected, but I 

 had reserved the fuller elucidation of them for an occa- 

 sion in which they should come before us under cir- 

 cumstances of such unusual development as greatly to 

 facilitate our researches. The weapons I speak of are 

 the cnidcB or nettling-cells. 



Look at this beautiful Scarlet-fringed Anemone 

 {Sagarta miniata), expanding to the utmost its disk 

 and tentacles in the clear water of the tank. I touch 

 its body ; instantly the blossom-like display is with- 

 drawn ; the column closing over it in the form of 

 a hemispherical button, which goes on contracting 

 spasmodically. At the same time see these white 

 threads which shoot out from various points of the 

 surface; new ones appearing at every fresh contrac- 

 tion, and streaming out to a length of several inches — 

 resembling in appearance fine sewing cotton, twisted 

 and tangled irregularly. 



Now the animal has attained its utmost contraction, 

 and the threads lengthen no more. But already they 

 are disappearing ; each is returning into the body by 

 the orifice at which it issued. It is, as you may see 

 by examining it carefully with a lens, gradually con- 

 tracting into small irregular coils, at that end which is 

 attached to the animal ; and these little coils are, one 



