DESCRIPTION OF A NEW CECID. 223 
We certainly saw the well-known Black Wood, but under the 
worst possible condition; a few common Lepidoptera were col- 
lected from the tree-boles, such as Larentia cesiata, Thera firmata, 
Ellopia prosapiaria (fasciaria), and the local form of Boarmia 
repandata; but the undergrowth was so soaking wet that nothing 
would rise from it, and we had to content ourselves by imagining 
what a nice lot of things we should have had, given fine weather. 
A few interesting plants were collected in Rannoch, viz., Pyrola 
minor, Carduus heterophyllus, and Comarwn palustre; and from 
the stony banks of the River Tummel, Thalictrum minus var. 
montanum, and Oxyria reniformis. 
Although during our run of seventeen days we had very bad 
weather for entomological work, stiil we left Scotland feeling we 
bad spent a holiday that will leave a pleasant memory of our 
trip to the Grampians for many years to come. 
6, Lewisham Road, Greenwich, 8.E., August 10, 1886. 
DESCRIPTION OF A NEW CECID. 
By Perger [ncusatp, F.L.S., anp R. H. Means. 
Cecidomyia clausilia, Bouche. 
Arter not a few fruitless attempts, I have succeeded in 
rearing the Cecid that affects one of our British willows (Salix 
alba), and lives in those little half-moon pads on the margins of 
its lanceolate leaves, as figured by Bremi, of Zurich, in the 
‘Transactions of the Swiss Natural History Society,’ in 1847. 
Bremi did not succeed, it appears, in rearing the imago; but he 
tells us that a single larva tenants each pad, and thus he 
supplies an important link in its economy. A previous notice 
of this Cecid was given us by Bouché, of Berlin, in 1834, so that 
priority of name naturally rests with him. Since 1847, H. Loew, 
Kaltenbach, and Rudow have given some particulars in relation 
to the home of the larva. In our own time Bergenstamm (1876) 
remarks in his ‘Synopsis,’ in relation to unknown and un- 
described imagines :—‘‘ These leaf-rollings are the work of a 
Phytoptus, and thus the Cecid-larve may be looked upon as 
inquilines.” It may be so, but it is not my experience. I may 
