Dorothy J. Jackson 99 



size and in distinctness of venation in different specimens, but no inter- 

 mediate forms between Figs. 3 and 1 have yet been observed. The 

 genitalia of the two forms have been examined and no differences have 

 been detected, and moreover in captivity brachypterous males have 

 mated with fully winged females. 



In a separate article a description will be given of the structure of 

 the two types of wings and of the modification of the metatergum in the 

 brachypterous form. 



Up to the present brachypterous specimens have only been taken in 

 two localities, from Wye, Kent, and in Ross-shire. In the former district 

 fully winged specimens predominated. In Ross-shire, around Evanton, 

 only the brachypterous form has been found^, but further north at 

 Kildary fully winged specimens have also been taken. The macropterous 

 form has been taken from the following locahties: Crowborough, Sussex; 

 Brandon, Suffolk; Tring, Herts.; Haslemere, Surrey; Kingussie, Inver- 

 ness-shire; Invershin, Sutherland. The distribution of the two forms 

 appears to have no relation to latitude or altitude, nor is the short 

 winged type rare in localities where it occurs. Thus at Swordale, Evanton, 

 about 500 feet high the latter form is abundant, yet at Invershin about 

 40 miles north near sea level, and at Balavil, Kingussie at an elevation 

 of over 700 feet, S. hispidula is equally common, but all the specimens 

 so far examined have been of the long- winged type. 



The Egg. 

 The eggs vary slightly in shape and size from 0-41 mm. by 0-37 mm. 

 or 0-46 mm. by 0-34 mm. to 0-49 mm. by 0-34 mm. They are similar in 

 colour and shape to those of S. lineata. The first laid eggs of S. hispidula 

 are pointed at both ends and twice as long as broad. 



The Larva. 

 The larva closely resembles that of S. lineata, but the colour of the 

 body, especially in the immature larva, is not as white as in that species, 

 but more translucent and greyish. Slight differences occur also in the 

 structure of the head by means of which it is possible to separate the 

 larvae of the two species, and it is hoped to describe these fully in a later 

 paper. No eye spots are present. The full grown larva measures about 

 6 mm. 



The Pupa. 



The pupa is similar to that of S. lineata and measures about 5 mm. 



^ Since writing the above a single ^^ of the fully winged form has been collected in this 

 locality. 



