PROPAGATION OF ACTINIA LACERA. 163 



Nineteen days subsequent to production, eight or 

 nine tentacula appeared on one which had fixed itself 

 by the base, as did others shortly afterwards ; their 

 shape was cylindrical, with originating tentacula, 

 irregular in number and dimensions the largest 

 having about twelve, the smallest about seven; in 

 short, the conversion of the corpuscle into a young 

 Actinia was complete. 



A remarkable deviation from the mode of propaga- 

 tion described above sometimes occurs among the 

 zoophytes we are now considering, of which the 

 Actinia lacera furnished Sir John Dalyell with an in- 

 teresting example. 



Whether, as in some other Actiniae, the young be 

 ever produced by the mouth, says Sir John, with 

 characteristic caution, I cannot affirm. The observer, 

 without ocular demonstration of the fact, might here 

 be led into error ; but during a large portion of the 

 year, particularly in August and September, not per- 

 haps excluding any month, the great irregularity of 

 the base of adult individuals of the Actinia lacera 

 cannot escape his notice ; it is unequal and ragged 

 to the eye, though all the other parts be regular, 

 smooth and even. 



This irregularity, at first hardly sensible, gradually 

 increases until it becomes such as is delineated in the 

 figure (PI. III. fig. 6, a). Next, we behold diminutive 

 fragments of the margin separating from the parent 

 animal (PL III. fig. 6, b), which consist of the ele- 

 ments of embryo Actiniae consolidated there, and soon 

 to be developed into independent existence. So rapid 

 is the progress of this development, that in a single 



