6o 'WHAT IS A SPFXIES:^' 



same thini:^ would have liappened to me on any scheme 

 of work.' ' 



The essentialh' subiective character of the results 

 reached by the systemalist stands out with remarkable 

 force in this as in other passai^es of Darwin's letters. 



A few )(\ars later, on Jul)- "o, 1S56, he. wrote to the 

 same frieiul : — 'I differ from him [I-y<^^ll] i^reatly in 

 thinking ihat those who believe that species are no/ 

 fixed will muliij)ly specific names : I know in my own 

 case my most frecpient source of doubt was whether 

 others would not think this or that was a God-created 

 Barnacle, and surely deserved a name. Otherwise I 

 should onl}' have thouL;ht whether the amount of differ- 

 ence and permanence was sufficient to justify a name.'" 



Disre^i^ardini;' for the moment the terni species, it is 

 convenient to consider the various groupings of individual 

 animals and plants. 



1. I'^orms havin«/ certain structural characters in 

 common distin<'uishin<^ them from the forms of other 

 groups. Groups thus defmed b)' the Linnaean method 

 of Dicii^Jiosis ma)- be conveniently called Sy)uh'aj^)ios/ic 

 {(Tvv, together ; Stdyicoai?, distinction). 



2. b^orms which freely interbreed together. These 

 may be conveniently called Syn(^a?}iic (a-vyy together ; 

 ydfio9, marriage). bree interbreeding under natural 

 conditions ma)- be termed Syu<^a))iy ; its cessation or 

 absence, /I syjij^cup/y (equivalent to the /lj)iixia of W'eis- 

 mann).-' 



' J.ife iiJid I.i/hrs, v()l. ii, p. 40. 



' Ihitl. vol. ii, \). 81. 



' The history of the term Synganiy, aUlioiigli brief, has been rc- 

 markaltle. By a curious coincidenee this very word was independently 

 projx)scd by my fiieml, Professor Marcus Ilarlog, of Queen's College, 

 Cork, in order to express that fusion of the essential reproductive elements, 

 or gametes, which has Ix^en generally known by the inconvenient and 

 in many ways misleading term ferlilizalic>n. Prof. Ilarlog suggested 

 the word (Sept. 14, 1903) in introducing a discussion on fertilization in 

 Section D (Zoology) at the meeting of the British Association at Southport. 

 The Report of the meeting (p. 693) only prints ihe names of the speakers. 

 I was not at the Southport meeting, and never heard the word until it 

 was suggested as suitable for my purpose by Mr. Arthur Sidgwick. 



