REPORT OF THE SOCIETY 103 



HATCHING 



A large number of eggs were laid loosely upon the surface of oak sticks 

 placed in cages where the gravid females were confined. The following obser- 

 vations relate to the hatching of these eggs rather than to those deposited in 

 the field. 



Incubation occupies ten to thirteen days. When ready to emerge the young 

 larva starts to cut its way out b^' nibbling a minute opening in the shell. This 

 is enlarged quickly from a small circle to an 'rregular hole, the larv^a working 

 at one edge of the aperture. The head is then partly pushed out and the work 

 of cutting away the chorion goes on while the body within is gradually uncoiled, 

 the legs being used vigorously to ass'st in the process. It is a matter of only 

 a few minutes before sufficient of the shell has been cleared away for the head to 

 emerge entireh^ and once this is done the larva proceeds to draw out the 

 rest of its body by short spasmodic struggles, clinging closely to the exterior 

 of the shell as it goes. It now begins to lay down a fine silken thread from 

 the egg case to the bark and at once becomes very active searching for cracks 

 or hollows nearby in which to enter. The time taken to emerge completely, 

 from the moment the first mark on the shell was observed until the larva was 

 outside, averaged twelve minutes. 



LARVA 



The average larva on hatching is 5.5 mm. long and 1 mm. wide. The head 

 is dark and the thorax dull reddish-brown; the body is flesh coloured on the 

 dorsal side and dull white on the ventral. A number of single, fine hairs appear 

 over the body situated laterally, several of extra length being on the head and 

 anal segment. 



By the end of the first season the lars^ a has attained a length of 20 mm. and 

 width 3.5 mm. The head is black and shining, the body pink in colour and 

 marked with a number of tubercles of a darker ^hade of pink. From each of 

 these a short fine hair arises. 



Larvae of the second season sihow considerable change in length and colour 

 scheme. The following is a description of a larva, likely a female, taken from 

 its 2nd year's hibernating quarters early in April 1921. Length 37.0 mm.; 

 width 6.0 mm.; head dark reddish brown and shining, retractile. Prothoracic 

 shield light brown with transverse crescent markings on the dorsum of the me.so- 

 thorax and meta-thorax. Two pairs of hairs on each side of thorax. Abdomen 

 faintlj"" pink, each segment bearing six reddish tubercles, four on the dorsum 

 which are arranged trapezoidally and one on each side near the spiracle. 

 Anal segment brown, true legs reddish brown, tarsi brown with dark hooks; 

 prolegs same colour as body, fringed with red hook-like attachments. 



A description of a specimen, probably a male, dug out of its second winter's 

 resting place, on IMarch 1st, 1921, is as follows: — Length 25 mm. approxima- 

 tely; width 5 mm. (broadest part of thorax). Head ajid mouth parts black, 

 shining, smooth, with few scattered hairs standing erect. Head retracting 

 into thorax. Thorax dull yellowish-brown, the meso—thorax and meta-thorax 

 gradually tapering to meet the first abdomi,nal segment. Each bears a brown 

 lunar marking, the cusps of which point toward the head. Abdomen is bright 

 pink or dorsum, except anal segment which is pale yellow and about the same 

 colour as the venter. Segments are well divided; each has four large, round, 



