100 
NTGGER. 
are clear and very shining, and tinged with yellow, and 
the upper ones have a dash of coal-hlack along the upper 
margin, which reaches three quarters of the way from the 
thorax to the tip of the wing ; the legs are yellow, spotted 
with hlack.* These flies do not taste the turnips, hut only 
come to them on family business : they deposit their eggs 
on the under side of the leaf, gluing them on the cuticle, 
as already described in the instance of the gooseherry-grub. 
In a very few days they were hatched; from the eggs 
had emerged the little caterpillars. On the 9th of August 
these little creatures swarmed on every leaf. I walked 
over field after field, and found them all in the same state. 
On Mr. Moline's farm, at Old Pond, three men were hoe- 
ing the turnips on a Saturday : 1 showed them the enemy, 
and told them that the turnips would be thin enough by 
Monday, without any hoeing; however, they were farmers' 
men, and "knowed better." On Sunday I could not 
get out as far as a turnip-field. On Monday I was again 
* This iusect is the Tenthredo centifoliae of Panzer, and was known as the 
parent of the nigger caterpillar even to Fabricius, who says " Larva tota nigra 
victitat in Brassica Kapa quam destruit." But perhaps the most remarkable 
fact in its published history is that a Norfolk farmer, a Mr. Marshall, connect- 
ed the yellow fly with the nigger or canker, in a paper in the ' Transactions of 
the Royal Society' for 1783. This author supposes that the fly is not a native 
of this country, but comes from beyond the sea, as it was said to have been ob- 
served by fishermen on the coast in "cloud-like flights." See Appendix 
B. After the date of the letter reprinted in the text, viz., August 15, 1835, 
our entomologists took up the subject with great zeal, and wrote about it in 
various papers, periodicals or Transactions, or made verbal communications at 
the rooms of the Entomological Society and elsewhere ; in fact the nigger was 
the same fruitful subject to entomologists in 1836, that the potato-blight be- 
came to botanists nine or ten years later: and I regret to say that the entomo- 
logists, like the botanists, left their subject very much as they found it. The 
nigger disappeared the following year, and the advice volunteered for its 
extermination was neglected, and has since been completely forgotten. — E. N. 
