XI 



flowers in the evening in exactly the same manner as the Sphingidae, are, like 

 these, strong, swift fliers and their structure answers to this. 



The manner in which Hesperidae hold their wings differs considerably in 

 different species, sometimes agreeing with that of the Heterocera, sometimes 

 more with that of the Rhopalocera. As to the first class there are some 

 species which, also when at rest, keep their wings spread out without folding 

 them together. This is the case with the South-American Antigonus species ; 

 as Seitz observes, and also e.g. with the Javanese Odontoptilum Angulatum 

 Feld. Most species, however, clap the wings together when at rest; but very 

 many of them do not spread them out quite flat when flying, but keep them 

 half raised, which is doubtless connected with, let us say, their springy way of 

 flying that as such resembles most the flight of the Sphingidae. 



That in which the Hesperidae show the greatest peculiarity may be observed 

 in these Lepidoptera in their larval state. The body of many larvae of the 

 Hesperidae is more or less transparent, a phenomenon which I do not remember 

 having met with to the same degree in other larvae. I should not be surprised 

 if this transparency caused a certain sensibility to light, which is the reason 

 why Hesperidae- caterpillars, mosdy live in rolled up or bent down leaves so as 

 not to be exposed to the full daylight ; for I also found that such larvae of 

 the Lycaenidae as are considerably transparent, though less than many 

 Hesperidae, lived inside leguminous plants and hence were not exposed to full 

 daylight. It is, therefore, quite common that the vas dorsalis of such larvae is 

 distinctly visible, sometimes so much so that the time of its lateral contraction 

 can exactly be observed. Very often, too, the testes of c? larvae lying on both 

 sides of the vas dorsalis stand out ver)' clearly as great, yellow, crescent-like 

 bodies ; through the transparent sides of some larvae numerous, thin, yellow 

 canals may also be seen. 



The heads of these larvae are peculiar, both in respect to their form and 

 especially in their colour, these heads, namely, are particularly large and 

 disk-like, the fore-side, however, somewhat convex and sometimes slightly 

 bifurcated at the upper-side. In many species they are very striking, so that 

 by this alone we can usually tell the larvae of this family at once, and besides 

 their size and peculiar shape this is especially to be ascribed to their striking 

 coloration, which is so characteristic in the different species, that they can 

 often be very well distinguished from each other by that alone, though, as we 

 shall see, mistakes are very easily made here. Now in this coloration the process 

 of colour-evolution is quite evident as we have already indicated above, and 

 leads to very peculiar phenomena. Sometimes the general colour of these heads 

 is red, orange, yellow in different tints, and sometimes also white, showing in 



