ALTERNATE GENERATIONS. 137 



dividuals similar to their parents ; T and they show further 

 that this brood, originated from eggs, may increase and 

 multiply by producing new individuals like themselves 

 (as in SyncaryneJ, or of two kinds (as in Campamdaria), 

 or even individuals of various kinds, all differing to a 

 remarkable extent one from the other (as in Hydr actinia), 

 but in no case resembling their common parent. None 

 of these new individuals have distinct reproductive 

 organs, any more than the first individuals born from 

 eggs, their multiplication taking place chiefly by the 

 process of budding ; but, as these buds remain gene- 

 rally connected with the first individual born from an 

 egg, they form compound communities, similar to some 

 polypstocks. Now some of these buds produce, at certain 

 seasons, new buds of an entirely different kind. These 

 generally drop off from the parent stock at an early 

 period of their development (as in Syncoryne, Cam- 

 pamdaria, etc.), and then undergo a succession of changes, 

 which end by their assuming the character of the pre- 

 vious egg-laying individuals. Organs of reproduction of 

 the two sexes are developed in them meanwhile, which, 

 when mature, lead to the production of new eggs. In 

 others (as in Hydractinia), the buds of this kind do not 

 drop off, but fade away upon the parent stock, after 

 having undergone all their transformations, and also 

 produced in due time a number of eggs. 2 



1 Polymorphism among individuals and fourth volumes of my Contrib. to 



of the same species is not limited to the Nat. Hist, of the U. S., and to 



Acalcphs ; it is also observed among which I do not allude here, as they 



genuine Polyps, the Madrepores for could not be understood without nu- 



example, and among Bryozoa, As- merous drawings. The case of Hy- 



cidiaus, Worms, and Crustacea (Lu- dractinia is not quite correctly repre- 



peci), and even among Insects (Bees), sented in the works in which that 



3 I have observed many other com- animal has been described. Respect- 



binations of a similar character among ing Physalia and the other Siphouo- 



the llydroicl Medusce, which I shall phora, see the works quoted above, 



describe at full length in the third p. 103, note 3. 



