40 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



habits— ^namely, Eaura orbitalis, Norton. Walsh, the 

 describer of its habits, says : " The gall is the lateral 

 bud of a twig enlarged so as to be twice or thrice 

 as long and thick as the natural bud before it 

 begins to expand in the spring, otherwise exter- 

 nally unchanged. Internally it contains early in 

 the autumn a homogeneous grass-green fleshy 

 matter which is afterwards consumed by the larva, 

 leaving nothing at last but a mere shell as thin as 

 paper, and i^artly filled with excrement. The gall 

 is monothalamous, sometimes one only on a twig, 

 sometimes three or more at irregular intervals — 

 rarely as many as three or four found out of 

 three or four consecutive buds." * 



In this last respect our native species does not 

 agree with the American. I have found several 

 long twigs with every bud converted into a galL 

 In Mugdock wood there are several willows (Salix 

 caprea) wdiich will bear no, or at least very few, 

 leaves next year, for all, or nearly all, the buds 

 have been killed, and in all probability these 

 bushes are more or less i^ermanently disabled. 

 Indeed, before I discovered the insect which ate 

 out the buds, I used to be jiuzzled to account for 

 so many willows being killed outright, or certain of 

 their branches only. 



Similar gall-buds are found on Salix aurita, and 

 as Eaura saliceti has been bred from the twigs of 

 that plant I have no doubt that further investi- 

 gation will show that it lives in the buds, only 

 boring into the twigs to become a pupa. I can, 

 indeed, adduce some evidence in sux3port of this 

 view. On the Kilpatrick hills I found a small bush 

 of Salix aurita the twigs of which had been very 

 much bored by the larva of E. saliceti, and many 

 of the leaf -buds were eaten out and enlarged. 

 In one or two buds I observed that the larva 

 had penetrated from the bud into the stem, where 

 it had spun its cocoon quite close to the galL 

 * Proc. Ent. Soc. PhlL, vi. p. 250. 



