swingle: merotypes 221 



as the true type (holotype), all others studied by the author in 

 describing his species being paratypes or cotypes. 



It is becoming increasingly evident that the views of an author 

 as to the limits of a new species are only too often considerably 

 modified or even completely changed by subsequent research. 

 This means that a paratype or even a subsequently collected 

 specimen considered by the author to be practically a duplicate 

 of the type cannot have anything like the .same value in taxo- 

 nomic work as the true type itself. 



It has not been adequately realized that the botanist often has 

 it in his power to collect a large number of specimens from the 

 plant that yielded the type and that if these specimens represent 

 homologous organs they may be practically equal to the type itself 

 for taxonomic study. This is because the plant body is usually 

 composed of homologous nodes or metamers 1 so that a branch 

 if selected with care, is almost absolutely identical with the type 

 specimen itself. In many cases it is even possible to multiply 

 such plants indefinitely by vegetative propagation, thereby pro- 

 ducing a practically unlimited number of such specimens. Trees 

 or shrubs often can furnish scores or even hundreds of specimens 

 practically identical with the type specimen and of very much 

 greater value from a taxonomic point of view than specimens 

 taken from other individuals, no matter how closely these latter 

 may resemble the type plant. 



In the case of trees, shrubs and perennial herbs, it is further- 

 more possible to collect fresh sets of specimens in subsequent 

 years from the type plant, thereby rendering it possible to send 

 specimens to all parts of the world. 



The word merotype 2 has been proposed to designate such speci- 

 mens and may be defined as follows: 



Merotype (^uepos a part ; tvtos a type) . A part of the individual organ- 

 ism that furnished the type specimen of a new species, such part usually 

 containing organs homologous to those represented in the type specimen. 



1 Cook, O. F., Dimorphic branches in tropical crop plants, Bull. 198, Bur. PI. 

 Ind., U. S. Dept. Agr., p. 8. Jan. 14, 1911. 



2 This word was first defined in this Journal 2: 212 as follows: "Merotype, 

 (fxepos a part; tvttos type) in taxonomy, a part of an organism that furnished the 

 type specimen of a new species," 



