268 MR. A. G. BUTLER ON THE GENUS EUPL02A. [May 8, 



7. A Monograph of the Diurnal Lepitloptera belonging to the 

 Genus Euplcea, with Descriptions of many New Species; 

 founded principally on the Specimens in the Collection 

 of the British Museum. By Arthur G. Butler, F.Z.S., 

 Assistant, Zoological Department, British Museum. 



(Plates XXIX., XXX.; 



The last synopsis of this genus was made in 1847 by Mr. E. 

 Doubleday, in his ' Genera of Diurnal Lepidoptera.' The number 

 of species at that time amounted to thirty-seven ; in the present 

 monograph it will be seen that the species are more than doubled. 

 A great proportion of them have hitherto been undescribed*. 



I have endeavoured in the present paper to arrange the species as 

 nearly as possible in a regular gradual series, so as to bring together 

 the more closely allied forms. I have also made an effort to sepa- 

 rate the numerous species into divisions and subdivisions, in order 

 to facilitate their determination ; these sections are, however, to 

 some extent necessarily arbitrary, owing to the variations to which 

 some of the species are subject, and to the difficulties arising from 

 the knowledge of only one sex. 



Genus Euplcea, Fabricius. 



Euplcea, Fabricius (Illiger's Mag. 1807), Horsfield, Boisduval, 

 Doubleday, Moore. 



Terpsichrois, Crastia, Salpi?ix, Didonis, Hiibner, Verz. bek. 

 Schmett. (1816). 



Danaus, p., Latreille. 



Datiais, p., Godart. 



Danaida, p., Guerin. 



Division I. 



Ala supra fusccc, plerumque elongatte et carulescenles ; apice 

 acuto, raro obtuso, plerumque maculis submarginalibus albis cceruleisve 

 serie duplici positis : subtus maculis discalibus caruleis aid albis, et 

 plerumque submarginalibus albis. 



Subdivision 1. 



Ala plerumque magna et, carulescentes : antica subtus maculis, 

 postica punctis discalibus, punctoque uno in cella posilo. 



1. Euplcea prothoe. 



Danais prothoe, Godart, Enc. Meth. ix. p. 177. n. 1 (1816). 

 Papilio midamus, Cramer, Pap. Exot. iii. pi. 266. f. A, B (1780). 

 Terpsicfirois alea, Hiibner, Verz. bek. Schmett. p. 16 (1816). 



* Several species, which I had overlooked whilst writing the present paper, 

 will be found in the Appendix. 



