The Scottish Naturalist. 235 



found by me on the twigs of oaks on Kinnoull were also 

 several specimens of " Oak-apples," but all of small size, the 

 largest not being over \ x / 2 inch in diameter. They form ir- 

 regular masses, smooth and soft externally when unbroken, 

 woody and hard internally, and made up of a mass of cells. 

 Those I got were brown in colour \ they are formed by 

 Teras terminalis Fab. 



Fagus sylvatica L. — The galls occur on the upper surface of 

 the leaves, from which they project, resembling rifle bullets, 

 contracted at the base, in shape. On the underside of the 

 leaf, below the gall, there is a low blister. They are about 

 yi of an inch in height, by half as much in greatest breadth. 

 Those which I have seen are naked, somewhat wrinkled, and 

 brown. They are monothalamous, and thin walled. The 

 most usual situation is in the axil of one of the chief veins, 

 but they may be on any part of the leaf. Mr. Tait first sent 

 me them from Inverury in April, and since that date I have 

 found them commonly on fallen leaves of beech, at Hazel- 

 head, near Aberdeen. Mr. Miiller informs me that the gall is 

 formed by Hormomyia pi/igera, and that, when it continues 

 long enough on the tree, it becomes covered with erect 

 hairs ; none of those which I have found has reached this 

 stage, however. The gall is readily knocked off the leaf; 

 the insect emerges by a hole in the side. 



Abies communis, L. — The galls described by me from this 

 tree are formed by Adeiges abirfis L. (b) I have also found 

 this year on this tree what I take to be galls of Adelges 

 strobilobius Kalt. They are terminal, of much smaller 

 average size, and the scales of which they consist are 

 smaller, making them look more compact than the former. 



Equisetum sp. — I must withdraw the excrescences found 

 on Equisetum from my list, as Mr. Hardy informs me that 

 they are merely vegetable excrescences, as he has found 

 them in the young stage, while full of sap. 



Flowering of Araucaria imbricata — An Araucaria imbricata which I 

 planted in my garden upwards of twenty years ago has this year thrown out two 

 strobiles or cones from the extremities of two of the top branches. When 

 purchased, it might be about four or five years old. The present age of the 



