19 
SESIA CULICIFORMIS. 
Plate V. Figure 6. 
This species varies from about ten lines to an inch 
or a little over an inch in the width of the wings. 
Male : front wings transparent, having a blue gloss when 
held to the light; blue-black on the upper edge, the 
bar the same, and the outer edge with a tinge of purple 
violet; the lower edge reddish towards the base. The 
hind wings have the fringe blackish. The body is blue- 
black, with a broad ring of red tinged with fulvous; 
the head and thorax blue-black; the tail-tuft black. 
The flight of this species is rapid. 
Localities for this species are York, Gravesend, Man¬ 
chester, Epping, Dublin, Coburg-road, and' other places 
near London. 
The situations where it is found are open places in 
woods. 
The dates of the appearance of the perfect insect are 
the end of May and the beginning of June. 
The caterpillar is pale dull yellowish white, the second 
segment dull yellow, the head brown. 
The date of the appearance of the caterpillar is in April. 
It feeds on the interior of the stems and branches of the 
birch, and also of the alder; and likewise, according to 
Mr. Westwood, on the wood of the plum and the apple. 
SESIA FORMICiEFORMIS. 
Plate Y. Figure 7. 
This very neat insect measures across from ten lines to 
eleven and a half. Male : front wings transparent, black 
