GENERAL EMBRYOLOGY. 



169 



of division passing in the direction of the long axis, or 

 forming an acute angle with it). 



Budding. In the case of budding, the products arising 

 from it are unequal. One animal maintains the identity 

 of the mother animal ; the outgrowth, on the contrary, the 

 bud, caused by local growth, appears as a new formation, 

 as the daughter individual. Yet the difference between 

 division and budding is bridged by intermediate condi- 

 tions; for, if we start with binary division, this is found to 

 approach budding in the same degree as the division prod- 

 ucts become unlike, so that the one takes on more and 

 more the character of a bud, the other retaining continu- 

 ously the character of the mother organism. Such transi- 

 tions are chiefly possible in the case of terminal budding, 

 where the buds appear elongating the maternal organism 

 at one end of the main axis. The character of budding is, 



O ' 



on the contrary, unmistakable, if the buds, by a new forma- 

 tion of their axis of budding, arise as lateral outgrowths 

 of the mother (Fig. 87), or, if from the same mother 



FIG. 87. A, Hydra grisea in optical section, with a bud in the long ax's ; also B, firit rudi- 

 ment of a bud. en, entoderm ; ek, ectoderm ; s, supporting lamella ; /', u-ntacle of the 

 mother animal ; /", tentacle of the bud ; /, stomach ; a, mouth-opening. 



numerous buds are simultaneously cut off (lateral and mul- 

 tiple budding) (compare Fig. 2ij. 



