THE AQUARIAN NATURALIST. 



on the 8th, and on the 10th only one remained, which 

 went to speedy decay. In the next place, a few buds 

 again protruded from the extremities on the 29th of 

 April ; several nourished on the tallest stem on the 

 4th of May, and the reproduction of them was again 

 general on the 13th of June. 



In short, from these and similar observations, it 

 has been proved : 1st, that the same twig may bear at 

 least six successive Hydrse ; 2nd, that the persistence 

 of a Hydra is from six to ten days ; and, 3rd, that the 

 interval required for the reproduction of the Hydrse 

 may vary from sixteen days to sixty. 



As regards the propagation of Eudendrium, Sir John 

 Dalyell gives the following interesting particulars : 



A splendid group of above fifteen specimens occurred 

 on a live mussel-shell. One of these, not 18 lines high, 

 bore 83 Hydrse, and another, somewhat taller, above 

 100. At least a thousand animated beings decorated 

 the group a wonderful assemblage of variety and 

 beauty on such a scale. 



Numerous clusters, like yellow ova, were inter- 

 spersed among the Hydrse, not within the circuit of 

 the tentacula, as with the Tubularise, but generally 

 around the exterior of the under surface or base of the 

 disc, though disjoined from it, and sometimes com- 

 pressing the Hydrse by their number and position. 

 But they were neither confined to any particular place, 

 nor peculiar to the finest specimens. Subjected to 

 the microscope, these substances proved to be of a 

 smooth, uniform surface, exactly resembling minute 

 ovoid plums, attached by short pedicles to some part 

 of the stem, but never within the Hydra. They were 



