The Scottish Naturalist. 159 



was flattened, green, and covered with bristly hairs. I did 

 not get it properly examined. Very scarce. 



Urtica dioica L. — The galls occur on the leaves, usually at 

 the top of the stem there is a cluster of them. They occur 

 one on each side, at the base of the leaf; they project most 

 below. Colour light green, surface rough and hairy, and 

 form irregular ; fleshy ; contain several larvae of Cecidomyia 

 urtictz. 



Salix fragtlis L. — The gall is on the blade of the leaf, and is 

 not connected with the midrib or veins. Form oval, and 

 much more prominent below the leaf; surface naked and 

 rough ; colour bright and red above, paler or green below ; 

 varying from }& to ^-inch in length, ^ to j^-inch in 

 breadth, and rather more in depth. It is monothalamous, 

 the central cavity being at first very small, and the walls 

 thick and irregular, but finally the walls are reduced in 

 thickness, and the cavity increases. Contains one whitish 

 or greenish saw-fly larva. 



Salix alba L. — Occur on the leaves singly, but from two to 

 six on each leaf. Form flattened above, conical below, 

 colour reddish-yellow. They are smooth and thin-walled ; 

 and each contains one hymenopterous larva. 



Salix caprea L. — (a) The galls in this, as in most of the other 

 willows, are on the leaves. They are well seen on the upper 

 surface, but project most below. They are smooth and 

 dark green above, covered with short yellowish hairs below. 

 Form irregularly conical ; structure very hard and woody. 

 They are monothalamous, snd open by a hole in the apex of 

 the cone below. All I found (in September) were empty. 

 (b) The galls are hardly seen on the upper sides, but pro- 

 ject much below. Structure soft and thin walled ; colour 

 green or yellowish-green ; surface covered with short hairs. 

 Each contains one hymenopterous larva. 



(To be continued.) 



Notes on Scottish Plants.— In the "Journal of Botany'' for November 

 there are one or two things of interest to Scottish botanists. One is a paper read 

 by the celebrated Robert Brown, before the Edinburgh Natural History Society, 



