68 RUOPALOCFAIA MALAYAXA. 



developed in either lieiiiisiihere." ' And the same author, iu a popuhu- manner, has drawn 

 attention to the migration of charauteristic Soutli American mammals to North America in 

 the Post-Pliocene epoch, f 



Now facts point to a similar conclusion respecting this distrihution of the butterflies. In 

 the European Eocene formations at Aix, in Provence, five fossil butterflies have been discovered 

 and described. Of these two belong to the SaUjrida- (to which the Murphhue are allied), and 

 Mr. Scudder, who has written an excellent monograph on Fossil Butterflies and particularly 

 studied these fossils, thus concludes :—" Three out of the five Aix butterflies tlierefore find 

 their nearest living allies in the Indo-Maiayan region, one is most closely related to forms now 

 found in Tropical America, and one is at home in its own resting place." \ Mr. Thiselton-Dyer 

 has pointed out similar coincidences with plants, especially in the tropical order Tenistrwmiacca', 

 " Out of thirty-two genera as many as five are represented in the Indo-Malayan and South 

 American floras," § and he inclines to the view of a transverse connection between the diflerent 

 branches of the tropical flora in the northern hemisphere during the early part of the Tertiary 

 period. || 



This group possesses considerable aftinity with the Satiirinw, not only by the ocellated 

 spots on the under-surfaces of the posterior wings, but also in the larval form, as shown by 

 the two figures (figs. 18 & 19). Both of these possess bifid tails, H as in that subfamily, though 

 one only has the head bicornuted.** The details of the larval forms of the different species in 

 this group are much desiderated. 



Six genera are found in the Malay Peninsula. 



■■'• 'Tropical Nature,' p. 330. 



f Ibid. The whole discussiou is carried out more fully in the same author's ' Geogr. Distr. Anim.' 



[ "Fossil Butterflies," Mem. Am. Ass. Adv. Scien. 1S75, p. 77. An excellent resume and description of the fossil 

 entomology of Aix has been given by Mr. Herbert Goss, iu "The Insect Fauna of the Keceut and Tertiary Periods," Proc. 

 Geol. Assoc, v. n. 6, p. '29 (1877). 



§ "On Plant-Distrib. as a Field for Geogr. Research." From Proc. Geogr. Soc. vol. xxii. u. G, p. 30 (1878). 



;| Ibid. p. 24. 



Note. — It has been generally assumed that a land-conuectiuu existed in Tertiary times between Europe and America. 

 Tims Prof. Boyd Dawkins, one of the latest exponents, declares ('Early Man in Britain,' p. '20), "The chief botanists of the 

 present time — Hooker, Dj'er, Saporta, Dawson, and Asa Gray — are agreed that the north polar region was the centre from 

 which the Tertiary floras have been dispersed over the New and Old Worlds;" and the same author (ibid. p. '23) considers 

 that tliere is evidence to prove the existence of a great Eocene continent, which including Britain (then connected with 

 AVestern France) extended to America by way of Iceland and Greenland, and was continuous with Norway and Spitzbergen. 

 " This great north-western continent, or northern Atlantis," existed through the Eocene and Miocene ages, " oiifering a means 

 of free migration for plants and animals, and it was not finally broken up by submergence" tiU the beginning of the Pliocene 

 age. Mr. .\. Tylor (Gc<d. Mag. vol. ix. p. 488), arguing that "the elevation of the Alps in the Miocene period must have been 

 acconi])anied by a much larger movement of depi-ession," thinks that probably " at the time a Miocene island or continent 

 (near Plato's Atlantis) in the Atlantic was suddenly depressed." 



An alternative hypothesis to that of now submerged land-couueetiou has been formulated by Mr. A. Tylor (Geol. 



Mag. vol. ix. 39'2), that in the Glacial period the ice-cap at the Poles was sufficient to reduce the level of the sea by at 



least 000 feet ; and Mr. Belt (' Naturalist in Nicaragua,' p. 266) was wilhng to propose a lowering of the level of the sea 



to 10(10 feet. 



': Tlie larv* of Morplw lacrtcs and M. cjiistrojihis, as figured by Dr. Burnieister (Descrip. I'hysiq. de la Eepubl. Argent. 

 — Buenos Ayres — vol. v. Atlas, pi. vii. f. 1, 2, 3, 4|, have the caudate anal appendages rudimentary, but still distinct. In the 

 representation of the larva of Marjihri acliilles by Mme. Merian (Metamorph. Insect. Surinamens. \<l. vii.), the structural 

 details of whicli have not been criticised by Dr. Burmeister in his reference to the same, these "bifid tails" are prominently 

 developed. 



■■■■ Dr. Bm-meister iu the text of the above quoted work (p. 189), in the diagnosis of his section Morphiilcr of his subfamily 

 Morjilioiilex, writes " Chenflles sans cornes sur la tete," which, though true of the genus Morpho, is certaiuly contrary to the 

 stiTicture of the larva oi Amaihiiaia phidiiqius as here figured. 



