496 
UliV. B. F. LINTON ON NORFOLK. RUBI. 
the drumming noise was heard, and it continued till it finished off with a 
sort of whiz, directly the upward sweep, by which the bird recovered itself 
was performed. 
“ By closely watching the bird it could he distinctly that the vibrations 
falling on the ear coincided exactly with the beat of the wings, which, 
assisted by the downward rush through the air were the ‘primary cause of 
the sound. The tail, however, was spread as I have already remarked, and 
to such an extent that it took the form of a fan, the lateral feathers being 
at right angles to the centre, and herein lies the secondary cause of the 
sound. 
‘‘ During the drumming beat of the wing, the quills are more drawn back 
than in the ordinary strokes (this can be observed if the bird be closely 
watched) , so that the atmospheric wave or air propelled by the powerful 
strokes of the wing is drawn through the rigid sabre-shaped and opened-out 
feathers of the tail, thus making the peculiar noise.” 
XII. 
NOTES ON NORFOLK RUBI. 
By Rev. E. F. Linton, M.A. 
Read 2'jth March, 1888. 
The Brambles of Norfolk well repay further research. I have not 
found time to stray much beyond the parish of Sprowston in 
search of them ; yet in that limited area I have found most of 
those which are here commented on, and I do not think the list 
is yet complete. I have to thank Professor Babington and 
Ur. W. 0 . Focke for ensuring the accuracy of the naming. 
Rubus plicatus, W. and N. Copses in Sprowston. This has 
been reported by Dr. Lowe from Wolferton in West Norfolk. 
R. INCURVATUS, Bab. Sprowston, in a wood-side hedge. 
Professor Babington accepts this, but says it is not quite typical. 
R. PYRAMiDALis, Kalt. Ill parts of Mousehold Heath. This 
is not what was known as R. pyramidalis, Bab., a name now 
dropped in favour of R. lomjiihiirsiger, Lees. 
