DEVELOPMENT AND REPRODUCTION 339 



plant. By proper treatment Klebs was able to produce zoospores in this alga at will, 

 or to grow the plant without their being formed. — Higher plants reproduce asexually 

 by means of outgrowths of various kinds, such as tubers, bulbs, etc. A branch, a 

 leaf, or a piece of root, may thus act as a reproductive organ. Many cultivated plants 

 are propagated by cuttings; advantage is taken of asexual reproduction in order to 

 maintain valuable varieties, which would be lost in many cases if propagated by seeds. 

 Related to propagation by cuttings is propagation by grafting or transplantation. 

 A bud or branch (scion) cut from one plant and inserted on another (stock) develops on 

 the new stem or root, retaining all the characters of the plant from which the bud or 

 branch was taken. Widely different parts of plants may be joined by transplantation. 

 In general, transplantation is possible only when closely similar species or forms are 

 involved. 



