150 Mr. E. Ernest Green's Remarks on 



sufficient justification for the erection of a new species. I 

 should prefer to regard it as merely a local race or — at 

 most — allow it to rank as a subspecies. But Mr. Kannan 

 goes so far as to suggest the propriety of erecting a new 

 subgenus for its reception ! 



Students of the Coccidae are beginning to realise that 

 too much reliance has been placed upon antennal characters 

 as a factor in classification. There is scarcely a single 

 species that does not exhibit variability in one direction 

 or another — in colour, size, or form, or in the structure of 

 one or more of its organs ; and it is in the antennae that 

 variation is most liable to occur. 



Mr. Kannan describes also what he considers to be two 

 abnormal forms from Java, which he believes to have been 

 similarly evolved from L. viride. From his description, 

 one of these (the round, convex form) would appear to be 

 a new species, while the other is probably identical with 

 L. africanum —a species which the author believes to have 

 been equally derived from viride. It would be interesting 

 to know whether these Javan insects have been submitted 

 to any expert opinion. 



But the most important part of Mr. Kannan's paper is 

 concerned with his hypothesis that Lecanium viride itself 

 is a direct mutant from Pulvinaria psidii. From the title 

 and sub-title of his paper, it may be judged that the author 

 considers that he has fully proved his case. I must confess 

 that his arguments — though most ingenious — are scarcely 

 convincing, and appear (to me) to be founded upon in- 

 sufficient evidence. 



The main argument, when analysed, appears to be as 

 follows : — 



1. Lecanium viride has suddenly evolved a distinct 

 variety with 3-jointed antennae. 



2. There are allied species, subspecies, or races in Africa 

 and Java. 



3. L. viride " is therefore clearly unstable." 



I. Pulvinaria psidii is subject to variation and has 

 allied forms in other countries. 



5. L. viride and P. psidii resemble each other super- 

 ficially and occupy the same regions. 



(i. Therefore L. viride is a mutant of P. psidii. Q.E.D. 



This, of course, is a very bald way of stating the case. 

 < iu i- author marshals a large array of evidence — or supposed 



