GENERAL NOTES- 
Hongkong, as has been observed already, is near the borderland of the Palaearctic Region, 
but the butterfly fauna is almost wholly tropical in character, and the two butterflies Clerome 
eumeus and Gerydus chinensis , peculiar to this part of China, belong to tropical genera. The 
only European species found here are Danais chrysippus , which occurs in S. Europe, Vanessa 
cardui (Painted Lady) and Polyommatus bceticus , all three insects of almost world-wide range. 
Danais is a tropical genus, some species of which are constantly extending their bounds, and 
D. chrysippus may perhaps be of comparatively recent occurrence in Europe. Charaxes is 
essentially a tropical genus, but has one species in S. Europe. The only characteristically Palaearctic 
genus except Vanessa is Argynnis , represented here by an insect which has a wide range in the 
Eastern tropics. 
Butterflies seem to be more dependent on special vegetation, and therefore climate, than, 
birds or mammals, and with these latter migration often takes places to a great extent; so that in a 
district on the confines of two Regions not separated by any formidable barrier, butterflies may 
perhaps be expected to show the affinity of the district better than other fauna. They no doubt 
migrate locally in some degree, and dominant groups are continually though slowly extending their 
range, as witness Danais archippus , Fabr., which Commander Walker—observing in 1893 that its 
foodplant, Asclepias curassavica , had spread throughout the Moluccas and Philippines and to 
Hongkong—notes that he did not find further from its original home than Ternate in the Moluccas. 
Since then it has occured (1901) in Hongkong, but apparently only once, when a $ and $ were 
taken the same day, evidently not long emerged from the pupa. D. chrysippus is now so abundant 
here that scarcely a plant of Asclepias is free from its larvae throughout the year, and this may be 
the reason D. archippus has not yet gained a footing, as the plant though widely scattered over this 
district is not very numerous in any one spot. But no movements, I believe, take place amongst 
butterflies comparable to those of birds. As regards the latter they are represented here by several 
Palaearctic as well as tropical genera, especially in the winter when (besides the ubiquitous Magpies 
and a Titmouse very closely allied to the English Parus major , which are resident and among the 
commonest birds) hosts of Pipits, Wagtails, Stonechats and other birds arrive and give quite a 
homelike character to the birdlife; the grey Wagtail being identical with the English bird, whilst 
the Pipits and Stonechat are merely Eastern forms of the English species, so close as to be hardly 
distinguishable. The butterflies, however, agree as might be expected with the vegetation—which 
must influence them even more than climate, since the larvae of many are restricted to one or two 
foodplants—and this is decidedly tropical, in spite of the everpresent fir-tree and the general absence 
of indigenous palms, except two or three species, which are, however, very common. The vegetation, 
at Shanghai on the other hand is almost wholly Palaearctic, and two butterflies very common there 
are either identical with or very close to the English “Clouded Yellow” and “Brimstone,’*' 
belonging to Colias and Gonepteryx , typically Palaearctic genera. 
