The Scottish Naturalist. 251 



SCOTTISH GALLS. 



( Continued from page 173.) 

 By J. W. H. TRAILL, M. A., 



Rhododendron ferrugineum L. — Dr. Buchanan White sent 

 me specimens of a gall on this plant, received by him from 

 the Rev. J. Fraser, Colvend, Kirkcudbrightshire. When they 

 reached me they were too much shrivelled for a good de- 

 scription, so I will quote from an article on this gall by Mr. 

 A. Miiller, in the "Gardener's Chronicle," of July 29, 187 1. 

 Those described by him were from Switzerland, but seem 

 identical with the Scotch specimens. He describes them 

 thus : — " Fleshy, fruit-like galls on the leaf, of about the size 

 of a raspberry, smooth. . . The galls, looking with their 

 glowingly red cheeks not unlike small-sized white-heart 

 cherries of irregular shape, were most conspicuous amongst 

 the sober, dark-green foliage of their foster-plants, which at 

 that time (June 23 and following days) only just began to 

 expand their lovely blossoms. The location of the galls 

 is either each separate upon a leaf, or else in the centre of 

 the top of a shoot, in which case the latter, instead of bring- 

 ing forth its branch of leaves or blossoms, produces a bundle 

 of more or less crowded galls, i.e., converted leaves or blos- 

 soms. An examination of many specimens showed that at 

 first they are filled with a spongy white substance, envelop- 

 ing a solitary egg, and that subsequently when this hatches, 

 the larva begins to feed on the surrounding matter, thus 

 gradually forming a chamber round itself. Taking into 

 account all that I have seen of this gall, I consider it to be 

 the production of a sawfly belonging probably to the genus 

 Nematus." The insect is yet unknown, and Mr. Miiller 

 advises sweeping the bushes in August and September fol- 

 ks capture. I trust the clearness and fulness of the above 

 description will be sufficient justification for the copiousness 

 of the extracts I have made from Mr. Miiller's interesting 

 notes on the subject. I was informed by Mr. Roy that in 

 July he was shown galls in abundance on a rhododendron 

 at Aboyne, in Aberdeenshire, probably R. ferrugineum 

 also; I have not as yet, however, seen specimens from this 

 locality.* 



* I remember seeing this gall long ago in Perthshire. — Ed. 



