ACROPTERIS. By Dr. A. Seitz. 275 



16. Family: Uraniidae. 



Under the name of Uraniidae a number of very heterogeneous moths are united which, for more than 

 one reason, must be considered as being some of the strangest of Lepidoptera. One groiip contains the most 

 brilliant species of all the Lepidoptera of the globe; magnificent majestic forms with golden or bronze or 

 brass gloss and the hindwing bearing long and delicate tails. The tired traveller crossing the hot Llanos of South 

 America and entering the dense shade of the valleys of the mountains, where foaming brooks have gnawed a bed 

 into the rocks, is enchanted by the crowds of marvellous Urania which rest on foam-bespattered walls of rock 

 with the wmgs spread out flat so that the metallic ornamentation of the wings glimmers in the sunshine. They 

 resemble the Swallowtails not only in facies, but also in their mode of flight, and their habits, and their beauty, 

 craving thirst and preference for day-light renders them superficially so similar to the Papilios that the. Uranias 

 might be regarded as the representatives of that family among the Moths. 



As a matter of course, all the similarities between Papilio and the genera Urania and Chrysiridia are 

 only the result of convergent development and have nothing whatever to do with so-called "Mimicry". For 

 that reason it is not possible to select a Papilio to which e. g. Urania leilus or fulgens bears a more special 

 resemblance. Mimetic similarity occurs, however, in one instance in the genus Alcidis; but in this case the 

 Uranid is the model which is imitated by a Swallowtail, P. laglaizei or alcidinus (cf. vol. 9, pi. 38 c). There 

 is indeed no necessity whatever for mimetic modification in the glossy golden Uranids. A moment's observa- 

 tion of their habits convinces one at once that these moths are almost absolutely protected against insectiv- 

 orous birds, whatever it may be that renders them immune; observe e. g. the East African C/ert/s. croesus when 

 it flies in the morning sun around the flowering Magnolia-trees entirely unmolested and challenging attack as 

 it were, or the species of Urania which flutter about before the eyes of the Tyrannid-birds which are seen wait- 

 ing for prey on every bush, or settle on the fissured rock of the mountain-valleys over which the water drizzles. 



This group of glorious moths, however, is not represented m the Palearctic Region. The dark col- 

 oured genus Nyctaletnon approaches Palearctic territory with one species, N. patroclus; it is still rather abun- 

 dant at Silhet in the Himalayas, but does not appear to reach Kashmir in the North-West, as far as that coun- 

 try belongs to the Palearctic Region. In farther India the species is very abundant in places, but already 

 in Southern China, at Hongkong, it was obtained by me surprisingly rarely, and does not appear to go much 

 north of that place. I did not meet with it at Shanghai, and it does not apparently reach Palearctic territory 

 in Western Chma, although one might expect stray specimens of such an excellent flier and wanderer to 

 occur in the Yang-tse valley. 



A further group, entirely dissimilar to the above forms, are the Microniiime, rather small and dull 

 white moth of a pronounced Geometrid facies. They strongly recall Ourapteryx, have pointed forewings like 

 these and their hindwings have often a short tail, this tooth frequently bearing the same peculiar markmgs 

 which are found on the wing-projection of Ourapteryx. Only of this group representatives are found on 

 Palearctic territory, namely 3 forms, which evidently are accpiisitions from the neighbouring Indian countries. 

 But as they extend to Amurland or the interior of China it is necessary to describe them here. 



The third and last group, which has only very distant affinities with the previous groups, especially 

 with the fii-st, and might better be treated as a separate family, has likewise the facies of Geometers, the species 

 being formerly considered to belong to the Loopers. The larvae with their 16 feet, and some minute differ- 

 ences in structure m the moths were the reasons for separating them from the Geometers and placing them 

 into the present family, already very heterogeneous without them. They are mostly small species, but some 

 genera contain also larger forms. The entire group has received the name of Epipkmime, the name bemg 

 derived from the principal genus, which contains almost exclusively very small forms. During the last 

 decade a very large number of species of Epiplema have been described as new. 



As the first subfamily (Uraniinae) is not represented in the Palearctic Region, we commence with 

 the second: 



b. Subfamily: Microniinae. 



1. Genus: Acropteris Hbn. 



Small, very slender and delicate moths with the frons relatively broad, the antennae filiform, the 

 palpi short and upturned, the legs long and strong, the tibial spurs long, and the abdomen slender, not 

 projectmg beyond the hindwing. Forewmg with the apex somewhat produced, the costal margin strongly 

 curved and the anal angle sharply marked and almost rectangular; the margm of the hindwing slightly and 

 very obtusely elbowed at the upper median vein. The colour is silky white, the wings above with thui golden- 

 brown longitudinal, oblique or transverse lines, the underside usually without stripes, shaded with grey. The 

 moths rest by day in thickets; they are usually very abundant, only being rarer at the boundary of their 

 area of distribution. 



