288 SPOLIA ZEYLANICA. 



Who can tell us what is the normal food of the common land 

 leech ? Only a few of the myriads of these little pests can ever 

 have the opportunity of tasting warm blood. 



The actual destination of the periodical migratory flights of 

 butterflies that are so conspicuous at certain seasons in Ceylon has 

 never been properly worked out, and the object of this movement 

 can only be guessed at. The solution of this problem would require 

 an army of observers, stationed along the route of the migration. 



What is the food of the common firefly ? It has been suggested 

 that they take no nourishment after attaining the adult winged 

 stage. But if that is really the case, why are they provided with 

 well-formed mouth-parts and jaws of a distinctly carnivorous type ? 

 In other insects, such as certain moths, that are known to take 

 no food in the perfect state, the mouth-parts are rudimentary or 

 completely atrophied. We know that the larvae of fireflies and 

 glowworms are carnivorous, subsistmg upon slugs, snails, worms, 

 and soft-bodied insects. But the firefly, in captivity, refuses such 

 food. They may sometimes be seen ccmgregated in thousands upon 

 the foliage of some tree, but I have equally failed to tempt them 

 with leaves or fruit, as might be expected from the structure of 

 their mouths. 



My endeavours to discover the breeding place of that unmitigated 

 nuisance, the " eyeflj^^," have, so far, been unavailing. I have been 

 assured that they must breed in fruit, as they can frequently be 

 seen swarming upon overripe plantains. But this assertion is due 

 to an error of observation. The tiny flies that so constantly frequent 

 such situations belong to quite a different family and species , whose 

 life -history is well knoAvn to entomologists. 



I could put endless other problems before you , but I have already 

 said enough to show you that the possibilities of useful discovery 

 that He withm your reach are by no means limited. We camiot 

 have too many careful observers. There are so many problems to 

 be solved, and so few to solve them. 



