220 THE ENTOMOLOGIST. 



and found that five of the moths, all females, were alive ; these 

 consisted of three ab. semiustana and two ab. nigrana. I next 

 obtained a large glass cylinder about 18 in. high ; in this I 

 placed in water two sprays of whitethorn and one of blackthorn, 

 introduced the moths, and covered the top of the cylinder with 

 muslin, feeding them on sugar and water, with which I saturated 

 a small piece of sponge. 



On April 7th, looking through the transparent side of the 

 cylinder, I saw, at the junction between the main stem of the 

 blackthorn spray and a twig, an unmistakable Tortrix egg. I 

 then took the sprays out of the cylinder and found hundreds of 

 ova deposited upon them. 



These were deposited by the females on all the sprays placed 

 in the cylinder, but although only one spray of blackthorn was 

 available, at least 90 per cent, of the ova were upon it. This 

 spray was crowded with them, mostly singly or in little clusters 

 of three or four. There were, however, two groups of over two 

 dozen each. The ova were usually deposited on the twigs, 

 generally underneath, but occasionally on the outside of the 

 undeveloped buds ; never on the leaves. I should mention that 

 the sprays had been kept in water in a warm greenhouse for 

 some weeks ; the whitethorn leaves were opened, and the trusses 

 of buds were exposed ; the blackthorn was partly in flower and 

 the leaves showed green. 



Desceiption of Ova. 



The outline is oval ; it lies, as is the case with the ova of all 

 the Tortrices with which I am acquainted, with its polar axis 

 horizontal. The length is -85 mm., the breadth '6 mm., and 

 the height '12 mm. ; the surface is granular, divided into a large 

 number of irregularly shaped cells by very fine raised lines ; it 

 is highly glabrous and opalescent ; it consists apparently of an 

 outer and an inner envelope. The outer envelope is transparent, 

 and it projects a considerable distance beyond the inner enve- 

 lope. The outer envelope is light grey in colour; the inner 

 envelope is white, and within this, again, is an irregularly 

 shaped nucleus which is reddish-brown in colour. The micropy- 

 ler area, which is very difficult to deal with in all horizontal 

 eggs, I was unable to examine. 



In five days after they were first observed the ova had 

 changed to reddish-brown, and they then harmonised exceedingly 

 well with the twigs on which they rested, and were very incon- 

 spicuous. The period from the depositing to hatching was about 

 twenty-one days. 



My experience, as narrated above, leads me to infer that the 

 ova are deposited in a state of nature in March or April on the 

 stems or twigs of their food-plant. 



