il SCIENCE—AD VER TISEMENTS. 
A NOTABLE BOOK. 
A Monograph, 
Structural and Systematic of 
the Order Oligochaeta. 
By 
FRANK EVERS BEDDARD, M.A, F.R.S. 
Demy 4to, with Plates and Illustrations. 
Price, $12.50. 
Times :—‘‘A most elaborate and exhaustive treatise, 
sumptuously printed and illustrated, on the anatomy, 
classification, and biological relations of an important 
order of segmented worms found in fresh water.’’ 
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Orford University Press, 
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Collections for Schools. 
ALPHA COLLECTION, twenty-five specimens in trays, con- 
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100 specimens, large size, $10.00. These specimens are 
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EXCELSIOR COLLECTION for high schools and colleges 
200 specimens, nicely mounted on wooden blocks, with 
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Loose Crystals. 
Small packages of free crystals for crystallographic study 
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proyal boxes of cabinet specimens by express or freight. 
ROY HOPPING, 
MINERAL DEALER, 
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SPECIAL NOTICE. 
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HOUGH’S “AMERIGAN WOODS” 
A publication illustrated by actwal specimens. 
WOODS FOR THE STEREOPTICON 
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Address R. B. HOUGH, Lowville, N. Y. 
