The Scottish Naturalist. 159 



For Larva : see De Geer, Me" moires, ii. 268, Tab. 38, fig. n-13; 

 Reaumur, Memoires, Tom. v. Tab. 12, fig. 17, 18. 



A LTHOUGH widely distributed, this species is somewhat 

 rare, both in the larval and perfect states I found the 

 former in Glen Fruin, Loch Lomond, towards the end of Sep- 

 tember, and subsequently a few were received from Dr. Bu- 

 chanan White, from Dunkeld.* I have taken the imagos at 

 Rannoch. In England it is found in the neighbourhood of 

 London ; and on the continent in France, Germany, and 

 Sweden. 



The larvae feed on the upper surface of the leaves of Alnus 

 glutinosa, making roundish holes, at first small, but gradually 

 larger and larger ; and may be observed lying motionless, with 

 the body pressed close against the surface of the leaves, the 

 colour of which harmonizes remarkably with that of their bodies, 

 which are consequently rather difficult to discover. They have 

 a habit when about to moult of resting on the head and anal 

 segments, the central portion being raised and clear of the leaf. 



The larva is onisciform, extremely flat ; the back being raised 

 and rounded, with the sides very thin, and almost transparent 

 and membranous. The head is narrow, and quite differently 

 formed from the rest of the saw-fly larvae. It rises sharply 

 from the back, with a hollow in the centre at the top, and the 

 face has a slope in the direction of the feet. When at rest it is 

 partly withdrawn within the overhanging folds of the second seg- 

 ment, with the mouth placed against the body. Its colour is 

 green, with the eyes black. On the top, at the back, are two light 

 brown splashes, and the mouth is of the same colour, but deeper. 

 A few short microscopic hairs are scattered over it. The feet 

 are glassy green, with black claws, and the fourteen claspers are 

 of the same colour and very short. The fifth and twelfth 

 segments are apodal. When the creature is motionless, neither 

 legs nor claspers are visible, being concealed by the 

 overhanging sides. The body in the centre is of a beautiful 

 dark shining green, with the sides, which are waved, whitish, 

 especially at the extreme edge, and fringed with long white 

 hairs. On the third and following segments, except the last 



* I have also seen larvae in Rannoch and elsewhere in the Highlands, where 

 this species seems pretty widely distributed. — Editor. 



