DOUBTFUL SPECIES. 43 



dnce from the same seed-capsule three distinct herma- 

 phrodite forms, bearing three different kinds of females and 

 three or even six different kinds of males. Nevertheless 

 these cases are only exao^gerations of the common fact that 

 the female produces offspring of two sexes which some- 

 times differ from each other in a wonderful manner. 



DOUBTFUL SPECIES. 



The forms which possess in some considerable degree 

 the character of species, but which are so closely similar 

 to other forms, or are so closely linked to them by 

 intermediate gradations, that naturalists do not like to 

 rank them as distinct species, are in several respects the 

 most important for us. We have every reason to 

 believe that many of these doubtful and closely allied 

 forms have permanently retained their characters for a 

 long time; for as long, as far as we know, as have good 

 and true species. Practically, when a naturalist can 

 unite by means of intermediate links any two forms, he 

 treats the one as a variety of the other; ranking the most 

 common, but sometimes the one first described as the 

 species, and the other as the variety. But cases of great 

 difficulty, which I will not here enumerate, sometimes arise 

 in deciding whether or not to rank one form as a variety 

 of another, even when they are closely connected by inter- 

 mediate links; nor will the commonly assumed hybrid 

 nature of the intermediate forms alwavs remove the difti- 

 culty. In very man}^ cases, however, one form is ranked 

 as a vaiiety of another, not because the intermediate links 

 have actually been found, but because analogy leads the 

 observer to sujopose either that they do now somewhere 

 exist, or may formerly have existed; and here a wide door 

 for the entry of doubt and conjecture is opened. 



Hence, in determining whether a form should be ranked 

 as a species or a variety, the opinion of naturalists having 

 sound judgm.ent and wide experience seems the only guide 

 to follow. We must, however, in many cases, decide by a 

 majority of naturalists, for few well-mai-ked and well- 

 known varieties can be named which have not been ranked 

 as species by at least some competent judges. 



That varieties of this doubtful nature are far from 



