24 REPRODUCTION 



extending into the pouch. This pouch grows and becomes 

 elongated, taking the usual shape of the body of hydra. 

 After a while it produces tentacles at the outer end, a 

 mouth breaks through, and we soon have a young hydra 

 attached to the mother. It has been formed purely by 

 the budding out of the mother. Food may pass into the 

 mouth either of the mother or the bud and finally get to 

 any part of the inner cavity. The bud grows both by 

 the food the mother captures and by that which it 

 captures for itself. It ultimately becomes free and closes 

 up the tube at the point where it was connected with 

 the mother, and depends for a livelihood on its own 

 exertions. One parent may have several buds of different 

 sizes attached to it at once. It may continue to produce 

 buds throughout the season. This condition is not very 

 different from the yeast, except that this is a many celled 

 animal; whereas the yeast is a single cell, and a plant. 



In many animals of the group to which the hydra 

 belongs, as in the hydroids and the corals of various 

 kinds, the buds do not separate from the parent stock. 

 By clinging together and by having each its own rate of 

 growth and division, they form most regular, interesting, 

 and varied colonies, which make them look like branching 

 plants. This has given them the name of zoophytes, or 

 plant-animals. 



5. Buds in Higher Plants. It is in the common plants 

 that the student is most familiar v/ith buds. On almost 

 every plant you have seen buds at the ends of stems, and 

 arising from the sides of stems in the angles of the 

 leaves. These side buds are very much like the buds we 

 have been describing in hydroids, that remain attached to 

 the parent and form complex colonies. In these plant 

 buds there are tissues which are continuous with similar 

 tissues of the parent stem and derived from them. These 

 buds, when they grow, develop more structures, as stems, 

 leaves, flowers, and the like, just like those that are to 



