IV 
CONTENTS. 
On the Planarih: of our Ponds and Streams. 
PAGE 
By E. Ray 
Lankester. Illustrated 
... 
388 
Ventilation and Ventilators. By the Editor. Illustrated ... 401 
Physics of the Brain. By B. W. Bichardson 
, M.A., 
M.D., F.R.S. 415 
Reviews of Books 
... 
66, 185, 299, 428 
Scientific Summary — A griculture 
... 
79 
Astronomy 
... 
80, 196, 309, 441 
Botany 
... 
87, 199, 313, 448 
Chemistry 
... 
90, 202, 317, 453 
Geology and Palaeontology 
... 
95, 207, 322, 459 
Mechanical Science 
... 
98, 212, 327, 464 
Medicine 
... 
100, 218, 330, 466 
Metallurgy, Mineralogy, and Mining ... 
... 
104, 215, 335, 471 
Microscopy ... 
... 
105, 223, 338, 477 
Photography ... ... ... ... 
... 
106, 227, 339, 479 
Physics 
... 
110, 230, 344, 483 
Zoology and Comparative Anatomy ... 
... 
114, 234, 349, 487 
