VOL. XXXIV, NO. 400 APRIL, 1900 
THE 
AMERICAN 
NATURALIST 
A MONTHLY JOURNAL 
DEVOTED TO THE NATURAL SCIENCES 
IN THEIR WIDEST SENSE 
CONTENTS 
I. The Relation of Fungus and Alga in Lichens GEORGE JAMES PEIRCE 245 
II. A Flagellated Heliozoan . : HOWARD CRAWLEY 255 
III. Reactions of Infusoria to Cisnicéla: A isim. . H.S. JENNINGS 259 
IV. The Basal Segments of the Hexapod Leg E LU L. B. WALTON 267 
V. Notes on the Psychology of Fishes . . + . -RW SHUFELDT 275 
VI. A New Museum Tablet > FRANK C. BAKER 283 
VII. The Lower and Middle Sonoran Zonos in Arizona and New Mexico 
TB 
VIII. Synopses of North-American —À VIII. The Caine 
Part II HARRIET 
IX. Reviews of Seco Litera Isl fibi pon pum Report of the Smith- 311 
sonian Institution, oen Notes— Zoólogy, Beasts, Lake Urmi, 314 
Reissner's Fibre, Preliminary List of the Mammals of New York, The 
Trait ied the Sandhill Stag, Structure in the Mammalian Egg, Bob, Our 
Native Birds, The Tree Frog, The Protoplasm of the Salmon Egg, 
akeyi of Invertebrates, A Recent Book on Insects, Sheep Tick, 
Nauplius Stage of Penæus, Sense Organs of Nereis, Breeding Infusoria, 
Swiss Infusoria, Growth in the Rhizopodan Shell, Abyssal Rhizopoda, 
A New Colonial Flagellate, Sporulation in Ameeba, e 335 
The Cyclopedia of American Horticulture = 
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GINN & COMPANY, PUBLISHERS 
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