80 FOSSIL BUTTEllFLIES. 



to have reached diflfcrent conchisions, for in his Revision de la Flore des Oypses 

 cTAix he states that the affinities of the eocene vegetation of Aix are with south- 

 eastern Asia and with Africa, and lists of analogous species are given, showing 

 that twenty-two Aix species are to be compared with similar types in Asia, and 

 forty with those of Africa. So that African fonns much surpass the Asiatic in the 

 eocene flora of Aix. This is particularly true, he says, with reference to the region 

 of Africa between Abyssinia and the Cape of Good Hope. "C'est la evidemment 

 le pays qui nous offre le tableau le plus rcssemblant de ce que devait etre le midi 

 de la France, et c'est aussi vers ce meme pays, ne I'oublions pas, que nous avons ete 

 ramenes par I'examen des autres elemens de la flore, specialement par la proportion 

 relative des deux grandes classes et des families predominantes." ' The African 

 element seems to be almost altogether wanting in the eocene butterflies, while the 

 Asiatic predominates. In a chart accompanying Count Saporta's pajjcr, however, 

 he represents the present limits of the principal genera noticed in the flora of the 

 gypsum of Aix by means of colored lines. These lines cluster remarkably along the 

 southern borders of Asia and extend over a large part of Africa and across the 

 ocean to America, and particularly toward the southern United States and the 

 Antilles. Based on the distribution of these principal genera alone, the flora of 

 the southern border of Asia would show a closer affinity to that of eocene Aix 

 than would that of any equivalent belt in Africa; and if we may suppose that our 

 relics of butterflies represent the principal genera then existing, we should trace a 

 somewhat similar chart, but for the entire absence of African types; for subtropical 

 American types mingle with those of the Mediterranean district and especially with 

 those of the Indo-Malayan region. Count Saporta shows in his memoir just 

 quoted, as before, that the relations of the eocene flora of Aix to that of the present 

 Mediterranean basin were more restricted than its relations to exotic types, but in 

 a letter to me he writes : "Ces affinites [les affinites presum^es de la flore d'Aix] 

 sont d'une part avec la region Mediterraneen, de I'autre avec I'Afrique et les Indes 

 orientales. Les affinites miocenes avec I'Amerique sont posterieures." These later 

 American affinities are, however, foreshadowed among the plants and also, as we 



> Ann. Sc. Xat., [51 Bot., XT, 311. 



