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POSSESSES MANY ADVANTAGES:
I. Accommodates the greatest v^ariation in pupillary
II. Easily and quickly changed from one stand to the other.
III. Will take a mechanical stage.
IV. Black and white backgrounds beneath the stage are always out of the way*
V. Has sufficient range of adjustment by rack and pinion to bring the objectives
to a focus considerably above the plane of the stage, thus permitting the
examination of objects of considerable thickness.
VI. May be used on three other types of stands supplied by us (see new 1914
Binocular Microscope No. 54 with one
pair of objectives and one pair ^jri\ i\i\
of ocularsj complete in cabinet.. ^OU.UU
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The Destruction of the Vitality of Cysticercus Bovis by
Freezing. B. H. Ransom 5
Summary of Two Years' Study of Insects in Relation to
Pellagra. Allan H. Jennings 10
Variation in Oxyurias: Its Bearing on the Value of a
Nematode Formula. Stanley B. Fracker 22
Observations on the Eggs of Ascaris Lumbricoides. Win-
THROP D. Foster 31
Dr. Nott's Theory of Insect Causation of Disease. Wil-
liam A. Riley 37
Rhabditin: Contribution to a Science of Nematology.
N. A. Cobb 40
Experimental Ingestion by Man of Cysticerci of Carnivore
Tapeworms. Maurice C. Hall 42
A Peculiar Morphologic Development of an Egg of the
Genus Tropidocerca and its Probable Significance.
Winthrop D. Foster 45
The Action of Arsenical Dips in Preventing Tick Infesta-
tion. H. W. Graybill 48
Eorhynchus: A Proposed New Name for Neorhynchus
Ham ANN Preoccupied. H. J. Van Cleave 50
The Helminthologtcal Society of Washington, Proceedings 52
The list of foreign collaborators is imperfect owing to present con-
ditions in the mail service and its publication is deferred until a later