PROCEEDINGS 
OF THE 
ROYAL SOCIETY OF EDINBURGH. 
SESSION 1906-7. 
No. IV.] VOL. XX VII. [Pp. 289-368. 
CONTENTS. 
XXX. Hydrachnidoe collected by the Lake Survey. By Mr Wm. 
Williamson. {Communicated by Sir John Murray, 
K.C.B.), 
{Issued separately October 3, 1907.) 
XXXI. Precipitated Sulphur. By Alexander Smith and R. H. 
Brownlee, . . . . . 
{Issued separately October 3, 1907.) 
PAGE 
302 
308 
XXXII. A Specimen of Helix pomatia with Paired Male Organs. 
By J. H. Ashworth, D.Sc.. Lecturer in Invertebrate 
Zoology in the University of Edinburgh. {Communi- 
cated by Professor J. C. Ewart, M.D., F.R.S. (With 
Plate, and Two Figures in the Text), . . .312 
{Issued separately October 4, 1907.) 
[Continued on page iv of Cover. 
EDINBURGH : 
Published by ROBERT GRANT & SON, 107 Princes Street, and 
WILLIAMS & NORGATE, 14 Henrietta Street, Coyent Garden, London. 
MDCCCCVII. 
Price Four Shillings and Sixpence. 
