44: THE AMERICAN MONTHLY [February, 



diatoms, duodenum of i-abbit, and head of ci"ane fly ; by reflected 

 light, hairs of sea mouse, peristomes of mosses and feathers of hum- 

 ming bird. 



C. C. Reidy exhibited diatoms, prepared in situ mounts, of Foram- 

 inifera graphically shown, with dark-ground illumination, produced 

 in an original manner by means of water-immersion in connection 

 "with the Abbe condenser. He also disphned slides of insects illustra- 

 ting structural anatomy. 



E. J. Wickson showed the diflerent forms and varieties of parasitic 

 and insect eggs, some of them of intricate structure and presenting an 

 ingenious adaptation of means to end. There were eggs round, disc- 

 shaped, and of octagon form, others flattened and provided with a trap- 

 door by which the newly hatched organism could make its debut into 

 the world, without the necessity of cutting through a tough but trans- 

 parent membrane that frequently j^resented all the colors of the rain- 

 bow. 



The human skin and the structures adjacent and connected with it 

 were shown by one of the exhibitors, while the slides prepared by him 

 and beautifully stained pi'oved of great value. One of the series illus- 

 trated the perspiration glands, together vs^ith the diflerent layers of the 

 skin through which they pass before emerging to the surface of the 

 body ; also, the subjacent areolar tissue and its connection with the 

 glands. ' 



A stained and mounted section of the human hair, shown in this 

 series, gave many quite a different idea from what they had held. The 

 hair follicle, the pigment cells, the diflerent layers of membrane sui'- 

 rounding the hair itself and the hollow central tube that conveys the 

 oil to the surface and keeps the hair smooth and glossy were all dis- 

 played. 



NOTICES OF BOOKS. 



Catalogue of Alicroscopes and Accessories. By James W. Qiieen & 

 Co., Philadelphia. 8°, pp. loS. 

 This is the seventy-second edition of Catalogue B, and is issued on 

 February i, 1890. It contains all the latest improvements in the Acme 

 Microscopes. Worthy of note are the full-page illustrations of Micro- 

 scope stands. There are some reductions in prices, such as on micro- 

 scopic cover-glasses. 



Physical Culture. By Prof. D. L. Dowd. 12°, pp. 300. So illus- 

 trations. 

 This book is to accompany the Professor's Home Exerciser, and so 

 the movements are mostly designed to aid those using the machine. 

 There are, however, a number of exercises which do not require any 

 apparatus whatever. Every movement is accompanied by an illustra- 

 tion, which shows the position of the body while in motion. There are 

 also several full-page illustrations, showing the various muscles and 

 bones of the human flgure. In a chapter on dumb-bells the author says 

 that a great deal of physical benefit can be derived from the use of 

 dumb-bells, but that usually more harm is done than good. The exer- 

 cises which he prescribes are especially valuable and free from objection. 



