ERYCINIDAE. By Dr. A. Sbitz. 619 



of the same finding-place can at any rate not be collected. Quite the reverse we experience in the American 

 Erycinidae. In almost all their species I was able to ascertain that the specimens of the same finding-place 

 exhibited the greatest lUveness, like the coins of the same stamping. There scarcely occur aberrations in colour- 

 ing or marking, and even larger or pygmean specimens are rarely found at the same place. The most striking 

 contrast to this is offered by the observation that even in two quite neighbouring habitats the specimens nearly 

 always show a constant difference from which one may precisely ascertain the place where they were found. 

 Similar peculiarities are noticed in South America also in some other groups of butterflies, such as Heliconius, 

 Melinaea, Mechanitis, and in dealing with the Ithomiinae it has been carefully avoided to assign new deno- 

 minations to the innumerable Mechanitis polymnia varying according to their habitat, and to give names of 

 a subspecies to those that are nothing but subordinate races. We must consequently also in the Erycinidae 

 avoid giving many new denominations, else we should have been induced to distribute more than 5000. The 

 Ithomiinae are very bad flyers, worse than any European day-butterflies, but still they are able to fly con- 

 stantly in the same direction and, therefore, to wander, whereas the greatest part of the Erycinidae seems not 

 to leave its birth-place at all *). Thus the single habitats, even when they are c[uite neighbouring, are without 

 any connection to each other, whereby such constant, though insignificant differences are formed, about 

 similar to the isolated Parnassius on the different mountain-peaks. If we consider that about 100 names 

 have been assigned to the one species Parn. ajjollo, we may imagine to what it would lead, if we were to deal 

 in a similar way with the 1000, often analogous Erycinidae; for about 50 names would have to be given to the 

 constant local deviations of the one Stalachtis calliope, if we were to consider every constant spot or shade, 

 for instance in a species of Parnassius, to be worth a denomination. 



Therefore we can neither attribute the rank of a subspecies to all the numerous, already denominated 

 forms of Erycinidae. If they are nevertheless registered here, it is done for completeness' sake. We shall preci- 

 sely determine the very numerous subordinate races being hitherto not yet ascertained by briefly indicating 

 the deviations of colours and markings, to which the single species or subspecies are subject. Within these 

 bounds most of the intermediate forms yet to be discovered may be placed, the habitat of which is at present 

 not yet ascertained. 



As we shall see directly, this characteristic variability occurring in but quite few (exclusively American) 

 groups of butterflies is to be explained by certain peculiarities of the habits, and we mention as one of the 

 most important biological singularities of the Erycinidae, the aversion to flying we have indicated above. Many 

 species, such as Sy7n7nachia, some very glaringly coloured Mesene, some Mesosemia seem to fly in the day- 

 time, if at all, only when being chased up, but otherwise to keep hidden under the leaf, so that, for instance. 

 Bates arrived at the conviction that they were able to make altogether only quite short flights. Fassl who, 

 next to Bates, has probably observed most of the Erycinidae in nature, writes about it (i. 1.): 



,,Many species of Erycinidae, especially also rare ones, seem to be bound to certain plants hy some 

 reason or other, apart from these plants being the food-plant. I often found certain species at intervals of 

 several days in 1 specimen each at the very same spot at the end of a branch." 



Fassl also furnishes a proof of it in his ,,Tropische Reisen" where he wTites about the rare Lymnas 

 thyatira: ,,I captured it at quite different seasons, but at one and the same shrub in 2 specimens." In the same 

 way Kaye found 2 specimens of Zeonia on the same bush in two different months, as he WTites ,,an evident 

 proof of its most local occurrence". The same habit I can prove for numerous Brazilian Erycinidae. As for 

 instance I found single couples of Isapis agyrtus at a spot of the road only a few metres in extent at the most 

 different seasons, always on the twigs of the very same tree, whereas I nowhere else came across this species 

 on more than 100 excursions in Tropical America. Exactly the same habit I experienced in Syrmatia, and 

 Me.sene sagaris of which I took both sexes at most any season, but always at exactly the same spot of the road. . 



It stands to reason that this aversion to flying cannot be absolute; and if certain species have never 

 been noticed swarming spontaneously, this may be due to their preferring a special hour for swarming. It 

 seems that the early dawn is often chosen, and Fassl ascertained for many species the early hours of the day 

 in which they go out in search of food or attend to their propagation. The Mesosemia which usually sit beneath 

 the leaves, sometimes come up to their upper surface and search the bushes by — as Fassl says ■ — ,, jumping 

 rather than flying" from one leaf to another, assuming a peculiar attitude of their wings (flattened dcmi hind- 

 wings and raised forewings). In other species the flights performed by them are extremely short, so that it very 

 rarely happens that one chances to observe them just then. Tharops pretus sometimes appears whirling on 

 top of a bush in the burning midday-sun, playing with its equals or small Thecla, right up into the an in order 

 to come down again after a few seconds and to hide itself. Quite similar is the habit of Ancyluris, the metallic 

 under surface of which exhibits a gistening coruscation when flying in the sunshine. After having flo'mi but 

 a few seconds the animals drop down on the tip of the bush and most skillfully run round the rim of the leaf 

 to its under surface to which they cling like the Geometrids. The Euryhia is seen almost only when it is chased 



*) As was supposed, the animals keep to the food-plants growing very sporadically. 



