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the same insect is described, or two forms wLicb ultimately piove to be the same 

 species and of the same sex are described, under two different names : both names 

 being published at the same moment, neither can be said to have priority over the 

 other. 



Mr. Worraald thought that, under such circumstances, the less appropriate name 

 of the two should be rejected ; or if one of the described forms was the ordinary form 

 of the insect and the other a mere variety, the name given to the ordinary form should 

 be retained. 



Mr. Dunning suggested that to this special case also were applicable all the 

 reasons which in ordinary cases had necessitated the introduction of the artificial and 

 conventional law of priority. The priority contemplated by that rule was doubtless 

 priority in point of lime, and not of place or position ; but when there was perfect 

 simultaneity, the ordinary rule of priority fiiled, and required to be supplemented by 

 some other and additional rule of easy and absolute application. Time failing to 

 answer the purpose, space may serve to supply a criterion. Though p. 5 and p. 50 are 

 published together, the former is before the latter; and in the case supposed the law 

 of priority in point of time may conveniently be supplemented by a secondary law of 

 priority in respect of place. 



Reverting to generic nomenclature, Mr. Dunning thought the result of the dis- 

 cussion might be summed up as follows: — (1) that the prevailing opinion was against 

 the existence of any such rule as that supposed by Mr. Kirby — that the first species in 

 a genus was the type ; (2) that the Members present were unanimously adverse to the 

 retrospective application of any such rule, which, if adopted at all, could not be con- 

 fined to any one group, but must be of general application to every branch of Natural 

 History; (3) that on the division of one genus into several, in the absence of indica- 

 tion of type by the founder, the author who divides the genus has a right to determine 

 to which division the original name shall be restricted ; and (4) that, in the view of the 

 majority, the original name ought to be retained (as of right, and not out of mere 

 courtesy) for some section of the original genus. To these conclusions Mr. Dunning 

 expressed his assent.* 



* I suppose we are all agreed that where the first describer of a genus indicates 

 which particular insect he regards as typical of the genus, that indication is binding 

 on future describers, and so long as the name is retained as the name of a genus at all 

 it must include the particular species so indicated. 



The indication of typicality may be either express or implied. If the latter, 

 evidence either intrinsic or extrinsic, positive or negative, is admissible to ascertain 

 the author's intention ; we may and ought to resort to any and every source or means 

 of information to determine what species presents the most perfect embodiment of the 

 idea which was in the mind of the founder, and possesses the most perfect develop- 

 ment of the characters which the founder has assigned as distinctive of his genus. The 

 publication of figures and dissections of a particular species ; the predominance of an 

 insect at the time and place when and where the author wrote, either by reason of its 

 size, beauty, abundance, destructiveness, or any other prominent trait; or the very 

 name given to the genus, may frequently serve as sufficient indication. Thus (to take 

 an instance referred to by Mr. Ki'by) the name Polyommatus shews that Latreille had 



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