LAOMEDEA. 65 



end, short and stunted at first, but tapering rapidly out into fine 

 flexible feelers, the stem branches, and we have a little Hydroid 

 community (Fig. 83), upon which, in the course of the following 

 spring, the reproductive calycles containing the Medusae buds will 



Fig. 83. 



iR . 82 . 



be developed, as in the case of the Eucope and Clytia. The 

 Tima passes through exactly the same process, though the shape 

 of the plauula3 and the appearance of the young differ from that 

 of the Melicertum, as may be seen in Fig. 78, where a single 

 head of the Tima Hydroid, greatly magnified, is represented. 

 By combining the above observations upon the development of 

 the Hydroids of the Melicertum and Tima with those previously 

 mentioned upon the young Medusa arising from reproductive 

 calycles in the Eucope and Clytia, we get a complete picture of 

 all the changes through which any one of these Hydroid Medusae 

 passes, from its Hydroid condition to the moment when it enters 

 upon an independent existence as a free Jelly-fish. 



(Laomedea amphora AG.) 



The Medusas of the Campanularians are not all free. On the 

 contrary, in many of the species they always remain attached to 

 the Hydroid, never attaining so high a development as the free 

 Medusas, and withering on the stem after having laid their eggs. 



Fig. 81. Planula of Melicertum ; magnified. 

 Fig. 82. Cluster of planulas just attached to the ground. 

 Fig. 83. Young Hydrarium developed from planula} ; magnified. 

 9 



