322 



BRITISH MOTHS. 



common weeds. Having tried the CATERPILLAK 

 with a great variety of provender, I can vouch 

 for its feeding on any plant sufficiently suc- 

 culent ; but when young its depredations are 

 mostly above the surface of the ground, and it 

 seems to delight in that particular part of a 

 plant which lies between root and stem, as I 

 have found numbers of young turnips and 

 carrotsdivided exactly at this spot, the upper 

 part being left to perish on the surface of the 

 ground. It also visits our flower-gardens. 

 Very often in a bed of China Asters 

 that favourite flower with all old-fashioned 

 gardeners the leaves of a plant here and there 

 will be found withering and curling up, and 

 you become aware that it is dying, and can't 

 tell why : just examine the stem where it 

 enters the ground, and you will find it com- 

 pletely decorticated ; the rind has been 

 gnawed off all round, and, the circulation of 

 sap being prevented, life is destroyed. This 

 is the work of the caterpillar of A gratis 

 Segetum : you pull up the aster to find the 

 enemy, but fail ; his depredations were com- 

 mitted in the night, and before daybreak he 

 has wandered far away, several inches, or 

 perhaps feet, and has burrowed like a mole 

 in the light friable earth that gardeners love. 

 It is tedious work looking for the mischief- 

 maker at night with a candle and lantern, and 

 picking up every caterpillar you may chance 

 to find ; and it is destructive to dig between 

 the plants : some gardeners sprinkle lime on 

 the ground, others sawdust, others soot, others 

 ashes, others salt, and others ammoniacal 

 water from gas-works ; but the result is far 

 from certain, and, therefore, unsatisfactory. In 

 August and September the caterpillar, which 

 has selected a turnip or a swede for its 

 food, goes further down : its operations are 

 now almost entirely subterranean, and its 

 chosen site is the very base of the turnip bulb 

 around the tap root which descends into the 

 earth. Here it excavates large and almost 

 spherical cavities, in which it resides hence- 

 forward, except during severe frost, not re- 

 turning to the surface unless its food fails : 

 when full-grown it is an inch and three- 

 quartergj or even two inches, in length, 



extremely stout, and its skin tight and shining : 

 when forcibly unearthed, it rolls itself in a 

 loose ring, but almost immediately afterwards 

 unrolls, and, if placed on the surface of the 

 earth, instantly buries itself with the activity 

 and skill of a mole. The head of the full-fed 

 caterpillar is stretched out on a plane with the 

 body, and is much narrower than the second 

 segment, flattened, and not notched on the 

 crown ; the body is cylindrical, the back 

 slightly wrinkled transversely ; the colour of 

 the head is pale dingy -brown, with two longi- 

 tudinal patches of dark brown on the face ; the 

 labrum and antennal papillae, are white ; the 

 body is pale smoke-colour, sometimes slightly 

 tinged with pink, or purplish-brown, and 

 always striped, although sometimes very 

 indistinctly ; the second segment has on its 

 back a dark and semicircular shining plate ; 

 and each of the other segments has ten cir- 

 cular, shining, dot-like spots, slightly raised 

 above the surface of the skin, and slightly 

 darker than the ground colour ; each of these 

 spots emits a small central bristle, and 

 each, also, is surrounded by a paler area ; on 

 the third and fourth segments these spots form 

 a pretty regular transverse series, but on the 

 fifth and following segments four of them are 

 ranged in a square or trapezoid ; one spot is 

 situated just above each spiracle, one below it, 

 and two others on each side of each spiracle ; 

 the spiracles themselves are very small and in- 

 tensely black ; the ventral area is the colour 

 of putty ; the legs are pale, and the claspers 

 putty-coloured and very small, not spreading 

 at the ends. These caterpillars turn to smooth 

 brown CHRYSALIDS in the ground, some in 

 October, but the greater number not until the 

 following May. Those which become chry- 

 salids in October emerge as perfect moths in 

 the course of a few days ; they rarely, if ever, 

 pass the winter in the chrysalis state, and it is 

 a very remarkable and hitherto unexplained 

 fact, but one which I have dwelt on at some 

 length in a paper read before the Entomological 

 Society, that the female moths which are dis- 

 closed in October and do not hybernate, are 

 almost invariably barren : I say almost, be- 

 cause I do not desire to press this theory 



