46 Observations on various Insects 



were given some excellent observations upon the economy of this 

 insect by M. Herpin, a translation of which I shall introduce here 

 without further apology : — 



" The standing crops of the cultivated clover {Tnfolium fraUnse, Linn.) are 

 attacked by a larva of the family of Curculionicte, which establishes itself in 

 the flowers of that plant, and which, after having pierced the calyx and 

 envelope of the young seed, gnaws and destroys the interior substance as 

 fructification progressively advances. On entering a field of clover while it is 

 in full flower, one perceives, without difficulty, a considerable number of 

 heads, of which the brown and withered corollas and the _^blackened calyces 

 show that they have long since done flowering. 



" On attentively examining some of the full-flowered clover-heads, it will 

 be observed that, among the large quantity of florets composing these heads, 

 many of the florets have already passed the time of flowering ; they are 

 brown and withered. 



" This premature and partial maturity of the flowers is commonly a 

 characteristic sign of the presence of the larva of the Apionwe are speaking of. 



" In truth, if we spread open, or carefully pull out, some of these withered 

 flowers, we shall perceive, near the base of tlie calyx, that is, near the point 

 of its junction to the stalk, a small black spot, or little hole, similar to that 

 made by a fine pin ; on slightly compressing the calyx, we shall see come 

 forth from this little hole a white, soft larva, rolled up, 1 or 2 millimetres in 

 length. 



" When this larva has arrived at its full growth, it forms, outside the hole 

 which it has perforated in the calyx, a globular white projection (at most 

 1 millimetre in diameter), which might be taken, at first sight, for a grain of 

 powder or plaster. 



" This larva afterwards changes to a nymph or chiysalis ; it remains in this 

 form for about 12 days. Towards the end of that period, one sees that the 

 nymph, which was originally of an ivory-white, is sprinkled with blackish 

 points ; the form of the rostrum, the eyes, and the legs of the insect are very 

 distinctly indicated under the envelope which covers them ; the rostrum 

 occasionally makes slight movements. 



" From this nynvph comes forth the little Apion apricans, which has long 

 been knoAvn to naturalists, who find it upon walls and in fields. 



" My clover was mown in full flower, then dried, although with some 

 trouble on account of the bad weather, and came again into leaf as usual. 

 What could become of the numerous larva^ housed with the clover? They 

 were probably suffocated by the heat, or stifled by the escape of carbonic 

 gas produced by fermentation and the stacking of the plant. 



" Ten or twelve days had scarcely elapsed after the housing of the clover 

 in the granary, when I perceived a great quantity of apions moving in all 

 directions upon the walls of the building, and making their way towards the 

 outside. The escape of these apions went on for eight or ten days. 



" Although the quantity of these little insects which escaped from the 

 granaries was innumerable (for the walls were covered with them), I could not 

 find a single one at some distance in the country, or even in the nearest plots 

 of clover." However, as these insects, as well as their congeners, shun the 

 daylight and conceal themselves, they might easily escape my investigations 

 through their extreme minuteness and deep green colour. 



" But it was a matter of the greatest interest to know whether the second 

 crop of clover which sprung up would be also infested by the apion. I 

 searched with a great deal of attention, and I eventually perceived that the 

 ripest heads were in their turn attacked by the same insect, and that finally 

 the second crop was not less injured than the first had been. 



