HYDEOZOA. 



35 



little use in procuring food. On watching a living 

 specimen, however, their efficiency is soon rendered 

 manifest. No sooner does a passing animal impinge 

 against one of these filaments than it is seized upon by 

 the lasso-threads, with which they are armed, and held 

 with mortal grasp. The mouth of the Coryne is not a 

 simple orifice, but a protrusible and flexible proboscis, 

 the extremity of which can be directed towards any 

 tentacle whereunto the prey happens to be adherent, and 

 thus the creature feeds itself exactly in the same manner 

 as the hydra described above. 



The Tube Hydra (Tubularia)* constructed very much 

 after the same plan as the preceding, 

 resides in a slender horny tube re- 

 sembling a straw full of mucilaginous 

 pith, rooted on a solid substance be- 

 low, and crowned by a living head, 

 resembling a fine scarlet blossom with 

 a double row of tentacula, and often 

 with pendent clusters like grapes. 

 Though perfect as a single stem, 

 it is seldom found solitary, from ten 

 to one hundred and fifty stalks are 

 generally crowded together, and con- 

 stitute a brilliant group, too gorgeously 

 coloured to be effectively portrayed 

 by art. The tallest specimens rise 

 thirteen inches high, and are gene- 

 rally found on dead shells. The 

 heads, or Hydrce, are not retractile 

 into the tube ; but, strange to say, are FIG. 2o.-ric.uRE OF TUBU- 

 continually falling off, and are re- 

 placed. Six have been seen to be thus reproduced, one 

 after the other, in six months. Dwelling among the 

 ravenous inhabitants of the deep, the delicate organs of 

 these defenceless beings are thus subject to continual de- 

 struction ; but what if they are mutilated, torn asunder, or 

 divided? They again rise unhurt. Wounds or lacera- 

 tions do not impair the vital principle, and thus abundance 

 is secured the widow's cruse is constantly replenished. 



The Sea-wreaths (Sertularice)^ are known to every sea- 

 side visitor. In these elegant productions the stem is 



* Tubulus, a little tube. 



t Sertula, a little ivreath. 



