70 MR. W. YARRELL ON AN INSECT DESTRUCTIVE TO TURNIPS. 
did not escape destruction, nor was it till the occurrence of the rains in September, after 
an unusually dry summer in many districts, that the mischief ceased. Some farmers who 
sowed for turnips again, immediately after the first rain, were as successful as the late- 
ness of the period would admit. It has been observed of those turnips that suffered in 
the leaf from the attacks of the black caterpillar, but not sufficiently to produce the 
death of the plant, that the turnip itself had become pithy and of little comparative 
value. So great was the failure of the turnip crop generally, that in some of the coun- 
ties on the coast where water-carriage was available, ship-loads of turnips were said to 
have been contracted for from the Continent to supply the deficiency. 
Of the degree of success which attended the various remedial measures adopted, I 
possess but little precise information. On a former visitation of this insect in the 
county of Kent, some farmers, it is stated, saved those fields in which the injury had 
scarcely begun, by turning in hundreds of ducks, with a boy going before them with a 
long pole, brushing the caterpillars off the leaves of the plants ; and it is added that it 
was an amusing sight to observe the ducks waddling after their courier, and devouring 
the insects with avidity, eyeing both sides of every leaf lest they should miss such 
palatable morsels. A heavy roller passed over the ground in the evening or night, when 
the caterpillars were at their feed and exposed to its effects, was another remedy resorted 
to. But that which was considered the most effectual was the strewing of quick-lime 
by broad-cast over the ground, and renewing it when dispersed by the wind. By this 
means, I was told, one field of turnips near Dover was saved, though surrounded by 
others that suffered greatly where no such preventative was employed. 
PLATE XIV. 
ATHALIA CENTIFOLIA. 
Fig. 1. The perfect insect, magnified. 
2. The same, of the natural size. 
3. The antenna of the male, considerably magnified. 
4, 5. The larva. 
6. The cocoon. 
7. The same, divided longitudinally and seen from the inside. 
8. The pupa, of the natural size. 
9, 10, 11. The same, magnified and seen in various positions. 
12. A Dipterous parasite (one of the Muscide) which, having completely de- 
voured the interior of a larva, has undergone its change to a coarctate 
pupa within the skin of the larva of the Athalia, portions of which (greatly 
stretched) are seen remaining on the outside of the Dipterous pupa, as well 
as the head of the larva which remains entire. An analogous instance, in 
Ophion Dorithea, has been recorded by M. Audouin in the ‘ Annales de la 
Société Entomologique de la France’ for 1834. 
