192 THE AMERICAN MONTHLY fJune, 



also wood destroyed by them. Mr. Udall exhibited scorpions 

 from Egypt. Mr. Hodgson showed a new microscope, and a 

 type slide of sponges prepared by Sinel. It showed Clathria 

 seriata, Halichondria panicea, Tethya lyncurium, Pachyma- 

 tisma johnstonia. 



J. E. Wright exhibited Zeiss's apochromatic objectives and 

 commended them as superior to all others. 



Sheffield (England) Microscopical Society. 



May 1, 1894. — Professor Denny gave a demonstration of the 

 " development of a bird." The structure and composition of 

 the egg were explained ; then, the development of the chick 

 embryo during incubation. A dozen slides of embr3'os of dif- 

 ferent ages were shown, these ranging from a few hours to five 

 days, the '' branchial clefts " being well marked in some. 



The following process of preparation of the slides was novel. 

 The embryo is washed in clean water twice, then placed in 

 osmic acid (1 per cent solution) for a short time. This fixes 

 and also stains a brownish-black; then soak in Muller's fluid 

 for 24 to 48 hours. Then clear in clove oil. Mount in balsam. 

 The differentiation in structure caused by the osmic acid is 

 complete, being far superior to hasmatoxylin or any other stain. 



NEW PUBLICATIONS. 



The Psychic Life of Micro-Organisms. — By Alfred Binet, 

 pp. 125, 12 mo., 25 cents. Chicago. Open Court Publishing Co. 



The author holds that all higher animals are merely aggrega- 

 tions of colonies of micro-organisms, each of which is endowed 

 with psychical attributes. He explains how these organisms 

 sustain themselves and seize food, resist poison, construct cells 

 and maintain life. 



Leitneria Floridana. — By William Trelease, St. Louis. Mo. 

 Missouri Botanical Gardens, pp. 26, })lates 15. 



This is the description of a new tree found in Missouri by B. 

 F. Bush in Nov. 1892. The plates are very fine and give illus- 

 trations of microscopic sections which we shall l)eglad to repro- 

 duce if Dr. Trelease will kindly loan the engravings. 



It is one of the lightest woods known. Its structure is loose, 

 tissues soft, heart wood entirely absent. 



