16 Mr. H. Eltringham's Jlfonograjjh of the 



geographically, since, to take a special instance, we have 

 at present no means of proving that joseudolycia astrigera 

 would pair and prove fertile with 'pseudolycia jyse^uloli/cia, 

 though there seems no reason to doubt the probability, if 

 each of these forms is ordinarily syngamic with the inter- 

 mediate form jJsc^^^o/T/cift i?"?m?iert. In the consideration of 

 evidences of such syngamy we must, I think, be prepared 

 to give full value to each particular point, and to consider 

 all the items in relation to the whole, rather than allow 

 ourselves to be bound, in all cases, by the indications of 

 one particular feature to the exclusion of others. 



Thus it may be assumed that constant differences in the 

 male armature are good evidences of specific distinction, 

 though when these organs are of a primitively simple 

 structure, similarity does not necessarily argue specific 

 identity. In some cases the structure of the female 

 genital plate enables us to confirm or modify views 

 based on that of the male organ. In some cases the male 

 tarsal claws provide valuable indications. Again, inter- 

 mediate types of pattern and colour leave no doubt as to 

 the specific identity of forms which, but for such connect- 

 ing links, would appear to be very distinct. Where I have 

 reason to believe that a particular form of a species is 

 peculiar to a certain geographical area, I have called it a 

 subspecies. Where, as frequently happens, a form of a 

 species seems liable to occur in various parts of that species' 

 range, and not to the exclusion of other forms, I have 

 merely styled such variations from the type as "forma'' thus 

 leaving the way open to the ultimate establishment of 

 whatever more particular definition the acquisition of 

 subsequent material and data may enable us to adopt. 

 I have avoided as far as possible the use of the word 

 " variety," since the limitation of its meaning is too ill 

 defined. I am aware that such a system is not infallible, 

 or indeed capable of universal ajDplication, since cases may 

 occur where a variety is a mere form in one locality, and 

 entitled to be regarded as a subspecies in another. 

 Nevertheless it is not without a certain convenience, 

 and, with our present conception of the evolutionary 

 nature of species-formation, the precise limitation 

 of what is called a " species " has necessarily lost much 

 of its importance, as compared with the recognition of the 

 degrees of affinity which appear to obtain between the 

 forms studied. In the case of the genus Acraea we have 



