178 



PSYCHE. 



any month in the year when many 

 common species, such as Etiploea core, 

 may not be seen laying their eggs. 



They are undoubtedly much more 

 plentiful in some months than others, 

 but this is because the largest number 

 of larvae come to maturity at those 

 times when succulent young leaves are 

 most plentiful and enemies least active. 

 Many species, however, pass through a 

 certain portion of the year, which is 

 unfavorable to them, in a state analo- 

 gous to hibernation. For example the 

 smaller Lycaenidae, such as Zi^era, 

 are not to be seen from June to August, 

 when the heavy rain would beat down 

 such feeble butterflies and drown their 

 larvae. They appear in September 

 and swarm for some months after. 

 The same is true of Hypolimnas niis- 

 ippus, perhaps because it feeds on 

 ground weeds, and the larva is liable to 

 be drowned by heavy rain. On the 

 other hand, H. bolnia and the majority 

 of the Nymphalinae and also the Papil- 

 ioninae are much more abundant dur- 

 ing the monsoon than at any other sea- 

 son. Bv the end of the year some of 

 them have become very scarce, if 

 they have not disappeared altogether, 

 and it is evident that those which feed 

 on deciduous plants cannot be in the 

 larva state from December to March 

 and later. The Pierinae, excepting 

 Nepheronia, are less abundant during 

 the rains than in the cold season, and 

 Atella pha/antka may be called a dry- 

 season butterfly ; its period of inactivity 

 is the monsoon. 



How each species tides over the par- 



ticular time which is unfavorable to it 

 is an interesting question on which our 

 knowledge is very limited. We have 

 proved that Pafilio nomitis regularly 

 remains in the pupa state from August 

 till the following March or May ; but 

 this is a peculiar case. In P. clytia 

 the pupa state is often prolonged for 

 weeks or months without regard to 

 season. But in the vast majority of 

 species the pupae in our cages hatch on 

 the due date as regularly as hen's eggs. 

 Yet there are good reasons for thinkmg 

 that it is in the pupa state that most 

 butterflies pass through the time when 

 nature is against them. It is also not 

 improbable that eggs laid at an unfavor- 

 able time remain unhatched till next 

 season. Lastly, some Hesperiidae hi- 

 bernate in the larva state. The larva 

 when full grown stops eating and shuts 

 itself up in a cell as if it were about to 

 become a pupa, but it does not actually 

 undergo that change for some weeks or 

 even months. We are not disposed to 

 believe that in this climate the imago 

 hibernates as it commonly does in Eu- 

 rope. 



Apart from hibernation, the length of 

 a larva's life varies a good deal accord- 

 ing to the supply of food. When ten- 

 der leaves are plentiful thej' grow fast. 

 Butterflies of strong build and powerful 

 fligiit, such as the Charaxes and the 

 larger Hesperiidae, live much longer in 

 the larva state than others. The dura- 

 tion of the pupa state, on the other 

 hand, seems to depend on little else 

 than size. Small Lycaenidae emerge in 

 a week, the majority of medium-sized 



