330 APPENDIX A. 



137. Hampson (Sir G. F.). (^ June 1897. 

 [Vide Hampson 127. Durrattt.'] 



"Alucita : the only species that seems to agree with the part of 

 the description 'fissis ad basin' \s pentadactyla." 



138. Walsingham (Lord). 10 Jujie 1897. 

 [Vide Walsingham 128. Durrant.^ 



"The original definition of Alucita is: 'ALUCITAE. Alis digi- 

 tatis fissis ad basin.' 



Mr Meyrick* thinks that moiiodactyla best conforms to this 

 description, but it seems impossible to admit that a species which 

 Linnaeus describes thus: 'alis patentibus linearibus indivisis,' could 

 have formed the type-conception of a generic description based on 

 the division of the wings into lobes. 



I have long been of opinion that the description was taken from 

 Reaumur's figure which is cited — and the figure would well account 

 for the name i>ionodactyla. 



Professor Aurivillius** writes that : ' if the characters are better 

 or in a higher degree developed in one species or in a group 

 of species than in others, I think that species or that group of 

 species must be held as typical' (he would apparently add 'despite 

 the action of subsequent writers '). For this reason he would reject 

 monodactyla and pentadactyla and fix the type as Jiexadactyla, follow- 

 ing Zeller, &c. who did not adopt the first good work on this genus, 

 viz. that of Latreille, who removed the most incongruous species, 

 hexadactyla, constituting it the type of his genus Orneodes, and thus 

 restricting the name Alucita to the five-lobed species. Linnaeus 

 himself proves that 'fissis ad basin' was not intended to mean that 

 the wings were cleft to the actual base of the wing, for in the de- 

 scription of didactyla he recognised the fact that both wings were 

 clearly defined ' anticis bipartitis, posticis tripartitis,' and surely 

 the use of ' digitatis ' explains that the Linnaean meaning was 

 really that the wings were cleft to a basal portion, and thus 

 became digitate. Digitus (and its derivatives) implies a special 

 reference to the human hand, and therefore the characters of the 

 genus are better developed in the five-fingered species than in 

 the abnormal 6 + 6-fingered species Jiexadactyla. One species 

 only was regarded as having five lobes on a common base, 

 and this species, pentadactyla^ agrees better with the description 

 ' digitatis ' than any other, and as all vary in the amount of 

 basal area this species agrees as well with the definition 'fissis 

 ad basin' as does any other. Linnaeus evidently overlooked the 

 fact that both wings were developed in pentadactyla, for he 

 described it thus : ' alis patentibus fissis quinque partitis niveis : 

 digito quinto distincto.' The species that were described with 

 greatest detail in Syst. Nat. X. were didactyla and pentadactyla. 

 [* Reply 129. ** Reply 88, 135. Durrani^ 



