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Academy of Natural Sciences — Exhibition of the Biological 

 and Microscopical Section. — The Biological aud Microscopical 

 Section of the Academj' of Natural Sciences gave an exhibition 

 of microscopes aud microscopic specimens, at the Hall of the Col- 

 lege of Physicians, on IViday evening, the 10th of June. As this 

 reception vras especially intended for professional men, the class 

 of objects displayed included many illustrations in pathological 

 anatomy and histology, of course chiefly iuteresting to physicians; 

 and about forty-five microscopes in all, each in efficient working 

 condition, were collected from the members and arranged upon 

 the tables. Among the specimens displayed, the Director of the 

 Section, Dr. S. Weir Mitchell, had on exhibition some preparations 

 of teeth, bone, &c., mounted by Professor Christopher Johnson, of 

 Baltimore, and also a collection of blood-corpuscles from diflerent 

 animals. Dr. William Pepper, Vice-Director, further illustrated the 

 subject by a series of blood-crystals. The amoeboid movement, 

 lately so famous in connection with both Cohnheim's theory of the 

 origin of pus aud Huxley's lecture on " ProtopLism," was well 

 shown by Dr. J. G. liichardson, the Secretary, with a power of 

 1300 diameters ; while the Corresponding Secretary, Professor 

 McQuillen, illustrated various departments of dental anatomy 

 and physiology by sections of teeth of man and animals (show- 

 ing, among other points, the interglobular spaces), and of bone 

 exhibiting the lacuna?- aud canaliculi. He likewise displayed 

 specimens of human muscle infested with trichina spiralis from 

 fatal cases of trichiniasis ; also the infecting swine's flesh. Pro- 

 fessor James Tyson had on exhibition a series of urinary de- 

 posits. Dr. Wm. F. Norris contributed some specimens of nerves 

 in the cornea, aud capillaries showing their parietal nuclei — 

 respectively gold aud silver staiuings — by the methods of Cohn- 

 heim and Kecklinghauseu. Some large sections of brain, kidney, 

 &c., were displayed by Dr. W. W. Keen, who also showed sundry 

 illustrations of nerve-structure. Dr. W. B. Corbitt exhibited a 

 valuable series of specimens of various malignant and other tu- 

 mours, collected in Grermany, and many of them classified under 

 the supervision of Professor Rokitansky. 



Mr. Walmsley and Mr. T. W. Starr each contributed a number 

 of mounted preparations. Mr. Zentmyer displayed, among other 

 instruments, one of his binocular microscopes. Professor J. A. 

 Meigs exhibited, with others, an injected specimen of the gall- 

 bladder, made by Dr. P. B. Groddard many years ago. 



Professor B. H. Hand arranged upon a side table his spectro- 

 scopic apparatus, and demonstrated the spectra of different metals, 

 and exj)lained this delicate method of analysis. 



