683 THE POPULAR SCIENCE MONTHLY. 



tion of the leading naturalists of Philadelphia, and quickly brought 

 him into communication with Cassin, Morton, Phillips, Bridges, Grid- 

 don, Gambel, Conrad, Vaux, Pickering, and other leading members 

 of the Academy of Natural Sciences. Community of interests led to 

 an intimate association with those gentlemen, and he was elected a 

 member of the Academy in July, 1845. 



His first published communication, entitled " Notes on White Pond, 

 Warren County, New Jersey," was presented to the Academy in Oc- 

 tober of the same year, and so active from that time was his work in 

 connection with the society that, at the annual election, in 1846, he was 

 elected chairman of the Curators, a position which he has since unin- 

 terruptedly occupied. With characteristic modesty he has frequently 

 declined the presidency of the society, and has contented himself with 

 the quiet, unostentatious performance of the very important duties of 

 chairman of the Curators. The respect and personal affection with 

 which Dr. Leidy inspires every one brought into intimate communica- 

 tion with him, together with his practical good sense and knowledge 

 of the needs of a large collection of objects of natural history, have 

 enabled him to act with great efficiency in his office for the good of 

 every department and interest of the society. Ke has been also a 

 number of years chairman of the Library and Publication Committees. 



Shortly after assuming his position in the university, Dr. Leidy 

 edited an edition of Sharpey and Quain's " Anatomy," with a view to 

 supplying the wants of his class while preparing a manual of his own. 

 The latter was published in 1861, and for clearness and accuracy of 

 statement and convenience of arrangement has not been equaled by 

 any other elementary treatise on human anatomy in the English lan- 

 guage. 



Dr. Leidy's earlier scientific work was confined to no specialty. 

 The whole field of Nature lay extended before him, and innumerable 

 were the objects of interest which engaged his attention. Hence one 

 is surprised to find how almost encyclopedic is Dr. Leidy's knowledge 

 of natural history. Although he has published little or nothing upon 

 either mineralogy or botany, his knowledge of both these sciences is 

 rather that of one who devotes himself specially to them than that of 

 the casual student. The pages of the " Proceedings " of the Academy 

 for 1845 and 1846, however, indicate that his favorite field of research 

 during that time was among the lower animal forms, and that his 

 microscope was often brought into use. The anatomy of spectrum 

 femoratum (Say), new species of entozoa, the mechanism which closes 

 the wings of grasshoppers, the situation of the olfactory sense in the 

 gasteropods, and new species of planarian worms, were among the 

 subjects upon which communications were published in rapid succes- 

 sion during the first two years of his connection with the Academy. 



In October, 1846, he recorded the occurrence of a species of trichi- 

 na in the hog, and stated that he could perceive no distinction between 



