July 15, 1904.] 



SCIENCE. 



83 



nourished ones. The efPect on the serum was 

 about the same. 



Other influences in the experiments were 

 carefully controlled. The observed effects 

 were due only in slight degree to the narcotics 

 and the conditions attending the operations. 



Demonstration of a New Portable Sphygmo- 

 manometer: T. C. Janeway. 

 Dr. Janeway's instrument was designed with 

 the object of secxiring a thoroughly portable 

 clinical sphygmomanometer, in which nothing 

 essential to accuracy should be sacrificed. It 

 employs the method of circular compression 

 of Eiva-Rocci, and Hill, with the 12cm. width 

 of armlet proved necessary by Von Reckling- 

 hausen. The special construction of the cuff 

 allows of adaptation to arms from 15 to 34 

 cm. in circumference. The original feature 

 of the instrument is the folding U-tube ma- 

 nometer. This is a jointed U-tube manometer 

 (copied from Cook), fastened to the under 

 surface of the box-lid, so arranged that, when 

 closed for carrying, it measures 10:| x 4f x IJ 

 inches, and with armlet and inflator weighs 

 2J pounds. The manometer is perfectly se- 

 cure when closed and stands firmly when open. 

 The tube-caliber is 3 mm. The sliding scale 

 is empirically graduated for each instrument, 

 to compensate for variation in the glass tub- 

 ing, and is accurate. All connections are of 

 heavy pressure tubing. For inflation a 

 Politzer bag is used, as by Erlanger, except 

 that one with valve is necessary to flll the 

 large armlet. The gradual release of pressure 

 is provided for by a stop-cock, with needle- 

 valve of special construction, the work of Mr. 

 Charles E. Dressier, who is making the 

 sphygmomanometer for sale. 



The method of use, as of the other modern 

 sphygmomanometers, is based on the criterion 

 of the return of the pulse after obliteration 

 (Vierordt), for systolic pressure, and is similar 

 to the Eiva-Rocci and its modifications. A 

 fair approximation of diastolic pressure may 

 also be obtained in most cases, using the 

 criterion of maximum pulsation (Marey, 

 Mosso). This is especially useful in cases of 

 aortic insufficiency, or marked hypertension. 

 For experimental work upon the systolic and 



diastolic pressures, it can not compare with 

 Erlanger's more elaborate and costly instru- 

 ment, but aims to serve the clinician by pro- 

 viding him with an accurate yet not bulky 

 or costly instrument, for general use. Stan- 

 ton's sphygmomanometer, which appeared 

 after this one had been begun, answers the 

 same purposes. The only criticism to be made 

 of it is, that 8 cm. width of armpiece does not 

 afford a guarantee of complete accuracy on 

 large arms. 



Demonstration of Cytological Preparations: 



Naohide Yatsu. 



Mr. Yatsu exhibited seven preparations 

 demonstrating important cytological struc- 

 tures found both in eggs normally fertilized 

 and in some treated chemically. He spoke on 

 the achromatic figure in mitosis, with special 

 reference to the morphology and cycle of the 

 centrosome. 



Preparation I. Metaphase of the first polar 

 mitosis with two centrioles at each pole (egg 

 of C ereiratulus) . 



Preparation II. Sperm nucleus with sperm 

 aster, in which each daughter eentriole has ac- 

 quired a new system of rays (egg of Cere- 

 hratulus). 



Preparation III. Anaphase of the first 

 cleavage mitosis, showing two centrioles in 

 each centrosome (egg of Cerehratulus). 



Preparation IV. Telophase of the first 

 cleavage mitosis, showing typical centrosomes 

 (egg of Ascaris, Professor Wilson's prepara- 

 tion). 



Preparation V. Mitosis without chromo- 

 somes in a late blastula (egg of Asterias, un- 

 fertilized and etherized). In one of the 

 blastomeres the aster is dividing, forming a 

 typical central spindle but devoid of chromo- 

 somes. 



Preparation VI. Cytasters (egg of Asterias, 

 unfertilized and etherized). Many cytasters 

 are found in the cytoplasm, some dividing, 

 some forming synthetic triasters. 



Preparation VII. Cytasters (egg of Cere- 

 hratulus, unfertilized and treated with a solu- 

 tion of calcium chloride). Many cytasters 

 have appeared, the first polar mitosis being 

 disturbed. 



