Contributions to the Natural History of the United States of America - Second Monograph; In Five Parts; I. Acalephs in General; II. Ctenophoræ; III. Discophoræ; IV. Hydroidæ; V. Homologies of the Radiata; With Forty-Six Plates #272057

Cambridge. The collection of scientific periodicals of the Smithsonian Institution is un questionably the largest on this continent, and but for the wise policy of Prof. Henry, the enlightened head of that establishment, the naturalists of America could not at this time make any investigations involving historical researches. Next to the Smithsonian Institution I have to mention the Academy of Natural Sciences in Philadelphia, the library of which has acquired the highest importance for naturalists, through the liberality with which Dr. Wilson has supplied its wants.