TABLE OF CONTENTS OF VOL. XVI, FART I. 
PAGE 
A summer resting stage in the development of Cyclops bi- 
cuspidatus Claus, . E. A. Birge and C. Juday, 1 
Some aquatic invertebrates that live under anaerobic con¬ 
ditions. . . . . Chancey Juday, 10 
Dissolved oxygen as a factor in the distribution of fishes, 
Chancey Juday and George Wagner, 17 
Notes on the fish fauna of Lake Pepin, George Wagner, 23 
Anatomical and histological studies of the digestive canal 
of Cimbex americana Leach (with Plates I-IV), 
Henry H. P. Severin and Harry C. M. Severin, 38 
Habits of the American saw-fly, Cimbex americana Leach, 
with observations on its egg-parasite, Trichogramma 
pretiosa Riley (with Plate V), ..... 
Henry H. P. Severin and Harry C. M. Severin, 61 
Description of a new subterranean Amphipod from Wiscon¬ 
sin (with Plates VI and VII). . S. J. Holmes, 77 
Concerning the organization of the spore mother-cells of 
Marsilia quadrifolia (with Plates VIII and IX), 
W. Marquette, 81 
Hybrid parts of speech. . . . Edward T. Owen, 107 
Electrolytic production of iodoform (with Plates X-XIII), 
Arden R. Johnson, 253 
Peculiar local deposits on bluffs adjacent to the Mississippi 
(with Plate XIV). . . George Hull Squire, 258 
■ On the suspension of solids in fluids and the nature of col¬ 
loids and solutions, . . . . F. H. King, 275 
The cold waves of south-central Wisconsin (with Plates 
XV-XXI). James L. Bartlett, 289 
