Insects. 9069 
snimmer crop at Heelsum, on the autumn crop at Voorst and Heerde, 
also at Dedemsvaart and in North Brabant in the neighbourhood of 
Moergestel, Bois le Duc and Langstraat. 
In 1857 the larva was again observed to cause considerable injury 
in the country about Ellekom, Heelsum, Dodewaart, Hattem, De- 
venter and Voorst. Dr. Wttewaall wrote in October of that year, 
“We think that Athalia spinarum will appear in great numbers next 
year, and, unless kept down by the wet weather, be the cause of great 
loss.” 
Nevertheless it appears that 1858 passed over without the usual 
turnip harvest having suffered much, so that the weather must have 
exercised some influence on the larva of our sawfly. 
I am also unacquainted with any record of its ravages in 1859. 
If the names of the villages and towns mentioned in these returns 
are noted, it will be-seen that the western part of our country appears 
to have been hitherto free from these attacks, and we thus come to the 
conclusion that it is most improbable that the fly should ever have 
flown over in great numbers from this country to England. We will 
now pass on to a description of the different states in which this insect 
is found ; in other words, of its metamorphoses. 
The egg is laid in a leaf of a turnip plant (Sinapis arvensis or 
Raphanus Raphanisirum) in an incision made by the saw of the 
female in the epidermis of the leaf. It is oval, white and sub- 
transparent, and is always deposited near the margin of the leaf. At 
a a, fig. J, pl. 9, is represented the position of two eggs on a turnip- 
leaf. In five days, or perhaps in a shorter time, if the weather is very 
favourable for their development, the young larve make their appear- 
ance; should the weather be very damp and cold, they are longer 
before they are hatched. On their first-emerging from the egg the 
little Jarvee are colourless and nearly transparent, with the exception 
of two little spots on the head; however, they very soon assume a 
pale green colour. A short time afterwards they begin to feed, eating 
several little holes in the leaf. Six or seven days afterwards they 
change their skin for the first time, when most of them are black or a 
very deep green. According to Curtis (‘Farm Insects,’ p. 48) they 
moult four times. 
After the third moult they have acquired the size of fig. 2. The 
appearance of the larva is then as follows:—The head is narrower 
than the body, shining, black and beset with a few very short stiff 
hairs; the eyes are placed in circular rings; beneath the eyes are two 
palpiform organs composed of six very short joints. The body is 
