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Defective Eyesight : The Principles of Its Relief hy Glasses. 



By D. B. St. John Roosa, M.D., LL.D., Professor Emeritus of Diseases of the Eye and Bar, Post Gi'aduate Med- 

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

 Manual 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- 

 stand and practice the rules for the prescription of lens for the improvement of defective sight. The book may 

 also be interesting to educated men in all departments of life, who desire to be informed as to advances that have 

 been made in this interesting subject, one which concerns such a large proportion of the human race. 



A Text Book of the Embryology 



Of Invertetorates. By Dr. E. Koksohelt, Pro- 

 fessor of Zoology and Comparative Anatomy in the 

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

 fessor of Zoology in the University of Berlin. 



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

 teropneusta, Echinodennata. Translated by Ed- 

 ward L. M-iRK, Ph.D., Hersey Professor of An- 

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

 University. 8vo. Cloth. Pp. 484. |4.00, 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, PalEeostraca. Trans- 

 lated by Matild.i Bernard. 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 Ittan ami mammals. By Dr. Oscar Hert- 

 wiG, Professor Extraordinarius 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 confined to the study 

 of mammals, there is so much of general embryology 

 within its covers as to give it a value as a general text- 

 book of vertebrate embryology. As such a text-book it 

 is of the greatest value to a student and it is safe to say 

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

 signed to give the student a general knowledge of ver- 

 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- 

 bryologists and is highly esteemed by them, especially 

 on account of the admirable presentation made by the 

 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 Trafts 



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 

 and important observations. It will pay any student of animal psy- 

 chology to read the book for the sake of these. ' ' — Professor Edward 

 Thobndike in Science. 



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

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

 The Chronicle, San Francisco. 



" 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 riACniLLAN COHPANY, Publishers, New York. 



