Bibliographical Notices. 479 



We next come to the treatment of genera ; and here Mr. Eorby 

 has made a conscientious attempt to introduce order into an ex- 

 tremely complex and unsatisfactory subject. But we cannot help 

 thinking that in many of the changes made an overstrained idea 

 of justice to old authors has been kept in view rather than the 

 interests of the living science. 



The source of this, we think, is to be traced to the absolute indif- 

 ference shown by Mr. Kirby as to whether a genus is intelligibly 

 defined by its author or not. With him (and he does not stand 

 alone) a genus is merely a name under which a greater or a less 

 number of species are arranged, and the practical working of the 

 system is that some one of such species is chosen as the type of the 

 genus, and the student is left to find out its generic characters for 

 himself ! Space will not permit us to pursue this uninviting subject 

 far ; but we will quote one instance of a name changed by Mr. Kirby 

 which will, we think, show how disadvantageously to the true inter- 

 ests of science the system he adopts may be made to work. 



For a well-known genus [wo were going to write of " ErycinidiB ; " 

 but this term is denied us] Mr. Kii'by adopts Hiibner's title Eiiselasia, 

 proposed in 1816 with the following valueless definition : — " Alle 

 riiigel oben zeichenlos, giattriindig; unten zierlich gezeichnet." In 

 1836 Boisduval gave the name Euriigona to an insect of the same 

 genus, one side of the figuve of which gives the formula of the 

 neuration. This latter name was adopted by Mr. Westwood in the 

 ' Genera of the Diurnal Lepidoptera,' where a full and elaborate de- 

 scription of the genus is given. According to Mr. Kirby's method, 

 if we want to find the generic characters of this group, what is the 

 process? After rejecting Hiibner's definition as absolutely worth- 

 less, we musi; turn to the ' Genera,' and then having found all we 

 want, we are stiU to reject the name there used ! But the change 

 does not stop here, for Mr. Kirby forbids us to use Mr. Bates's sub- 

 family name Eurygoninse, proposed in an exhaustive catalogue of the 

 species of this fami'y, and thrusts Euselasia again before our eyes in 

 the form oi Eiiselastince. Without defending the use made in the 

 ' Genera ' of some of Hiibner's names, we still think that the estimate 

 then made of the ' Verzeichniss bckanr ^er Schmetterlinge ' was a 

 proper one, and that to many of Hiibner's names the courtesy attach- 

 ing to manuscript names was alone dre. The obligation to use them 

 ought not to be imperative ; and they certainly ought not to be made 

 to supersede well-characterized generic titles. 



In closing these remr rks we will only call attention to one other 

 matter which we cannot help thinking also shows a certain amount 

 of misapprehension as to the nature of genera. Mr. Kirby, in the 

 fii'st rule he imposes upon himself, says, " The name of every 

 liomogeneous genus, if not a synonym, or previously used in zoology 

 or botany, should be retained for some part of it." 



This rule has puzzled us much ; and Ave aro at a loss to discover 

 what its meaning is ; for if a genus is homogeneous, it appears to us 

 that the necessity, nay, even the possibility of dividing it ceases to 

 exist. 



