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Packard's Guide to the Study of Insects, and a Treatise on those 

 Injurious and Beneficial to Crops. For Colleges, Farm-schools, 

 and Agriculturists. By A. S. Packard. With 15 plates and 

 670 wood-cuts. Ninth Edition. 715 pp. 8vo. $4.50 net. 



■ Outlines of Comparative Embryology. By A. S. Packard. Copi- 

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Zoologies. See American Science Series. 



.- i.kins's Outlines of Electricity and Magnetism. By Chas. A. Perkins, 

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Pierce's Problems in Elementary Physics. Chiefly numerical. By 



E. Dana Pierce, of the Hotchkiss School. 194 pp. i2mo. 

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*Price's The Fern Collector's Handbook and Herbarium. By Miss Sadie 



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 Randolph's Laboratory Directions in General Biology. 163 pp. i6mo. 



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Ramsen's Chemistries. See American Science Series. 



Scudder's Butterfliss. By S. H. Scudder. 322 pp. i2mo. %\.ionet. 



Brief Guide to the Commoner Butterflies. By Samuel H. Scudder. 



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 — —The Life of a Butterfly. A Chapter in Natural History for the 



General Reader. By S. H. Scudder. 186 pp. i6mo. 80c. net. 

 Sedgwick and Wilson's Biology. See American Science Series. 



*Step's Plant Life. By Edward Step. Popular Papers on the 



Phenomena of Botany. i2mo. 148 Illustrations. $1.00 net. 



Underwood's Our Native Ferns and their Allies. By Lucien M. Under- 

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Williams's Elements of Crystallography. By George Huntington 

 Williams, late Professor in the Johns Hopkins University, 

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Williams's Geological Biology. An Introduction to the Geological 

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Woodhull's First Course in Science. By John F. Woodhull, Pro- 

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/. Book of Experiments, xiv + 79 pp. 8vo. Paper. 50c. net. 

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Zimmermann's Botanical Microtechnique. Translated by James Ellis 

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