ON ANIMAL LIFE 



107 



dusae in all stages of development (Fig. 3), some 

 still in the condition of minute buds, in which 

 no trace of the definite Medusa-form can yet 



Fig. 2. — Bougainvilleafruticoaa; natural size. (After AUman.) 



be detected ; others, in which the outlines of 

 the Medusa can be distinctly traced within 

 the transparent ectotheque (external layer) ; 

 others, again, just casting off this thin outer 

 pellicle, and others completely freed from it, 

 struggling with convulsive efforts to break 

 loose from the colony, and finally launched 



