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Defective Eyesight : Tlie Principles of Its Relief by Glasses. 



By D. B. St. John Roosa, M.D., LL.D., Professor Emeritus of Diseases of the Eye and Ear, Post Graduate Med- 

 ical School and Hospital ; Surgeon to the Jlanhattan Eye and Ear Hospital, etc., etc., author of "A Clinical 

 Manu.al of Diseases of the Eye ; " " Ophthalmic and Otic Memoranda ; " "A Practical Treatise on the Dis- 

 eases of the Ear;" "The Old Hospital and Other Papers; " "A Vest- Pocket Medical Lexicon,'' etc. 

 ■ ^ ' Cloth. 12mo. $1.00, net. 



No pains have been spared to make the manual a complete guide to the practitioner who wishes to under- 

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A Text Book of the Embryology 



Of Invertebrates. By Dr. E. Kokschelt, Pro- 

 fessor of Zoology and Comparative Anatomy in the 

 University of Marburg, and Dr. K. Heidek, Pro- 

 fessor of Zoology in the University of Berlin. 



Vol. I. Porifera, Cnidaiia, Ctenophora, Vermes, En- 

 teropneusta, Echinodermata. Translated by En- 

 WAKD L. Mark, Ph.D., Hersey Professor of An- 

 atomy, and W. McM. Woodwokth, Ph.D., Harvard 

 University. 8vo. Cloth. Pp. 484. 54.00, net. 



" The book has been in the hands of zoologists all 



over the world and is recognized as an excellent and 



indispensable reference book." — Professor Jacob Reig- 



HARD in Science. 



Vol. II. Phoronidea, Bryozoa, Ectoprocta, Brachio- 

 poda, Entoprocta, Crustacea, Palaeostraca. Trans- 

 lated by Matilda Beenard. Revised and Edited, 

 with Additional Notes, by Martin F. Woodward, 

 Demonstrator of Zoology, Royal College of Science. 

 8vo. Cloth. Pp. xv+375. |3.00, net. 

 The second part of a work described in the review 



quoted above as "so well done that the book is likely 



to remain for many years without a rival." 

 Part III. is in preparation. 



Of JHan and Mammals. By Dr. Oscar Hert- 

 wiG, Professor Estraordinarius of Anatomy and 

 Comparative Anatomy, Director of the II. Anatom- 

 ical Institute of the University of Berlin. Trans- 

 lated from the Third German Edition by Edward 

 L. Mark, Ph.D., Hersey Professor of Anatomy in 

 Harvard University. Second Edition, with 339 

 Figures in the Text and 2 Lithographic Plates. 



8vo. Cloth. Pp. xvi-|-670. ?5.25, net. 

 " While it is in details largely contined to the study 

 of mammals, there is so much of general embryology 

 within its covers as to give it a value as a genei'al text- 

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 that at the present time there is no text-book so well de- 

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 tebrate embryology as the present one." — Science. 



"The translator's work has been exceptionally 

 well done, for the rendering is both accurate and 

 smooth. . . . The work has been welcomed by all em- 

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 author of many of the most interesting problems with 

 which their investigations have to deal." — British Med. 

 and Surg. Journal. 



THE 



DAWN 



OF 



REASON 



Mental Traits 



in the 



Lower Animals 



" Any one interested in the progress of comparative psychology 

 must wish well to a man who, without the incentives of the professed 

 naturalist, makes it a labor of love to watch animal life. I, for one, 

 shall welcome such ... a very con'.iiderable number of suggestive 

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 dike in Science. 



"The author is a bold and independent thinker, as shown by a 

 previous work . . . and his observations profoundly interesting."— 

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" In this little book are gathered together a great many interesting 

 data . . . the author has observed and experimented for himself and 

 in many respects his conclusions are striking and novel. " — Literature. 



JAMES WEIR, Jr., 

 M.D. 



Author of 

 "The Physical Corre- 

 lation of Religious 

 Emotion and Sexual 

 Desire. ' ' 



Cloth, cr. 8vo, 

 $1.25. 



THE HACniLLAN COHPANY, Publishers, New YorI<. 



