1 8 Appendix. 



' Bory de Saint Vincent says that, according to Degeer's calculation, a single female in 

 one year can produce 23,600 individuals ; another estimate gives 75,000 individuals as the 

 offspring of twelve pairs of weevils in a hectolitre of grain, each of which would consume 

 three grains in the year for its own subsistence, or about 12 per cent. Other naturalists 

 confine their estimate of the offspring of twelve pairs to about 6,000. This last figure, 

 however, abundantly suffices to confirm the worst fears that the farmer has of his enemy.' 

 ' The grain, whose interior is devoured by the weevil larva, is not in any way changed 

 outwardly ; it is in fact impossible to distinguish it from the sound grain : if, however, one 

 puts it in water it swims, while sound grain sinks.' 



' The males live but a few days after they have fertilized the females. The female lives 

 until she has done laying her eggs, and as she has many eggs to lay, she lives longer than 

 the male ; if there is no grain in which to oviposit she becomes torpid, waking up how- 

 ever when grain is supplied, being probably revived by its odour, she then lays her eggs 

 and dies.' 



' It is thus specially in the larval state that the weevil is injurious to the grain. The 

 only perfect insect that devours it being the female engaged in oviposition, an operation 

 which goes on throughout the whole of the summer, until the cold deprives the insect of 

 the necessary activity. The beetles then quit the heap of grain, and seek shelter in the 

 holes in the walls, and in the cracks in the floor, where it is difficult to discover them : 

 with the first warmth of spring they appear to again copulate, oviposit, and die.' 



' The odour of many vegetable substances, such as hops, elder flowers, rue, lavender, 

 and coriander, is objectionable to the beetles and makes them quit the wheat ; also decoc- 

 tions of these plants and also of ivy, box, and larkspur, spread through the granaries, 

 produce the same effect, Valmout de Bomare^ however, considers all these methods useless 

 or impracticable ; Duhamel also has found that the beetles live quite contentedly in wheat, 

 enclosed in a case that had been painted with oil of turpentine ; according to Duhamel 

 sulphur in vapour is the only thing to destroy the beetles, and this gives a flavour to the 

 wheat.' 



' In some provinces of France millet seed is mixed with the wheat, as the insects attack 

 millet seed in preference to wheat, so that by later sifting out of the millet seed, which is 

 smaller than the wheat, the beetles are got rid of.' 



' Stirring the grain, and aerating it, by means of forcing air through tubes in the heap 

 of wheat, are recommended, on the ground that the insect loves warmth and quiet. The 

 most effectual method of cure is, however, to destroy the affected wheat and to put hay into 

 the granary.' Mons. Menault asserts that now that grain is less stored than before, the 

 ravages of the insect are becoming less serious. — {Translated from the account given by 

 Ernest Menault, in his " Insectes Nuisibles a I' agriculture," Paris, 1886, page 8.) 



'Sitophilus {Curculio) granarius, Linn. — (Der Schwarze Kornwurm). Beetle attacks 

 rye, wheat, and maize. Introduced from the East, it probably acclimatised itself in 

 Southern Europe, of which, however, nothing is known positively ; in Germany it only 

 appears in granaries, mills, bakehouses, &c. ; sometimes in immense numbers.' 



' The beetle is red to black brown in colour, antennae and legs somewhat lighter (rust 

 red); length, not including the proboscis, is If breadth f; the thin slightly curved 

 proboscis is about the same length as the thorax, and bears at its base, immediately in 

 front of the eyes, the elbowed antennae with six jointed stock, and long egg-shaped, indis- 

 tinctly jointed terminal club. The thorax is longer than broad, slightly narrowed in 

 front, flat above, and beset with large produced dots, which leave, however, a smooth 

 longitudinal medial stripe. Elytra are, together, the same width as the thorax, at the 

 outside a third longer than their combined width, with parallel sides, rounded off at the 

 posterior end, and not covering the posterior plate of the abdomen, flat above, deeply 

 striated with pits, the intermediate spaces being smooth. Tibiae each terminating in 

 claw, the front ones having small notched teeth on the inner edge. Tarsi four-jointed.' 



