638 



PHYSIOLOGY. 



PITA. 



tained as urainido-benzoic acid, and in that of 

 the dogs nearly 20 per cent. Thus is rendered 

 probable another example of a synthesis by the 

 addition of cyanic acid within the animal body, 

 since under the conditions which there prevail 

 no other mode of formation for uramido acids 

 is yet known. To ascertain in which organ 

 uramido-benzoic acid is formed, Salkowski ex- 

 perimented upon a rabbit from which the kid- 

 neys had been extirpated, and found the acid 

 in the blood, liver, and muscles. Ligaturing 

 the ureters caused no increase in the amount 

 of acid found. It is, therefore, evident that 

 uramido-benzoic acid is not formed in the kid- 

 neys, and, since Von Schroeder has found that 

 ammonium carbonate is converted into urea in 

 the liver, it is probable that the former process 

 is also carried on there. 



Physiological Literature. The year's list of 

 new publications is not distinguished by the 

 presence of any book of great importance in 

 physiology. A considerable number of vol- 

 umes and papers have appeared, particularly 

 in Germany, where this work has been most 

 industriously carried on, embodying the results 

 of special studies, but little is to be found in 

 them that adds materially to our knowledge 

 of general principles, or points to any startling 

 discovery. 



Among the American publications of more 

 general interest are Brubaker's " Text-Book 

 of Physiology " ; a translation, by Meade Smith, 

 of L. Hermann's u Experimental Pharmacolo- 

 gy " : and Dr. Gradle's (Chicago) treatise on 

 u Bacteria and the Germ-Theory of Disease." 

 Mallet has published a paper on the " Deter- 

 mination of Organic Matter in Potable Water." 

 White has discussed the question, u Is the Blood 

 a Living Fluid ? " R. S. Henry has reported 

 upon his new studies in the " Crystallization of 

 Haemoglobin." Chittenden and Ely have in- 

 vestigated the " Alkalinity and Diastatic Ac- 

 tion of Human Saliva." We notice also mono- 

 graphs, all embodying the results of experi- 

 mentation, by M. L. Holbrook on the " Ter- 

 mination of Nerves in the Liver " ; Minor on 

 " A Case of Color-Blindness for Green " ; 

 Muybridge on the " Attitude of Animals in Lo- 

 comotion " ; Mitchell and Reichert on the 

 " Venom of Serpents " ; and Sternberg on the 

 " Germicide Value of Certain Therapeutic 

 Agents, and on the Micrococcus of Gonorrhoeal 

 Pus." 



The English list furnishes a fourth edition 

 of Dr. Michael Foster's " Text-Book " ; a trans- 

 lation, by McAlister, of Ziegler's " Text-Book 

 of Pathological Anatomy and Pathogenesis " ; 

 Coats's " Manual of Pathology " ; Klein's " His- 

 tology " ; Malley's " Microphotography " ; stud- 

 ies by Wells on "Indian Snake-Poisons"; 

 Lawes, Gilbert, and Warrington on the chem- 

 istry of the "Fairy Rings"; Pavy, Johnson, 

 Rolfe, and Oliver, on " Urinary Tests and Tests 

 for Albumen "; Elsberg, Bower, and Gardiner, 

 on " E 5 rotoplasm " ; Geddes on the " Cell The- 

 ory " ; Harris, Norris, and Ray Lankester, on 



the " Blood " ; Gaskell on the " Function of 

 the Cardiac Tissue " ; Huddicombe on " Respi- 

 ration " ; Budwin on the " Supposed Poison- 

 ous Alkaloid in Human Saliva " (in which he 

 contradicts some conclusions of Gautier) ; Gar- 

 rod and Cook on " Uric Acid " ; Stone on 

 the " Influence of High Temperature on the 

 Electrical Resistance of the Human Body"; 

 L. Brunton on the " Nature of Inhibition, and 

 the Action of Drugs on it " ; Poulton on the 

 u Origin of Taste-Bulbs " ; Stone on " Singing, 

 Speaking, and Stammering" ; Brown on " Pho- 

 tography of the Larynx and Soft Palate " ; 

 Blomfield, Dowdeswell, and Wiltshire, on the 

 " Reproductive Organs " ; Ringer on the " Ef- 

 fects of Dilution and Concentration on the 

 Action of Poisons " ; Lauder Brunton on the 

 " Temperature-Modifications of the Action of 

 Drugs " ; Dowdeswell on the " Action of Pa- 

 paine with reference to the Occurrence of Mi- 

 cro-Organisms in the Blood " ; Ringer and 

 Sainsbury on the " Action of Chloral, Opium, 

 Bromide of Potassium, and Barium Chloride " ; 

 Williams on "Experiments upon Bacteria 

 with Disinfectants " ; Klein and Ray Lankester 

 on " Bacteria " ; Crooke on " Bacilli in Scarlet 

 Fever " ; and by Cheyne, West, Gibbes, Smith, 

 Williams, Green, and Dreshfield, on the " Ba- 

 cillus of Tubercle." New apparatus have 

 been described by Shenstone, Vachcr, Glaze- 

 brook, Thelfall, and Warner. 



The German list includes four hundred and 

 thirteen titles, and a small number of papers 

 in French are registered. 



PITA. The pita-plant differs from an aloe 



E roper (the European aloe belongs to the lily 

 imily), and also from the cactus, with both 

 of which it has been confounded. Richard 

 Whiteing speaks of the planters of Mauritius 

 cultivating it for its valuable fiber, and names 

 it a species of aloe (Aloe Mexicana) ; and Dr. 

 Trowbridge, United States consul at Vera 

 Cruz in 1880, said, in speaking of a variety of 

 this plant, if not actually the same species: 

 " There is a species of cactus here commonly 

 called ' pita,' some of the fibers of which are 

 sixteen feet long. It is strong and silky, and 

 capable of being drawn into threads, from 

 which, gossamer webs might be woven. In 

 fact, a few months ago, a Vera Cruzan sent 

 some of the fiber to England, and had a few 

 handkerchiefs made, which were extremely 

 beautiful, and appeared more like silver tissue 

 than linen, and were quite strong." Pita is 

 generally known as the American aloe or 

 agave-plant (Agave Americana). It belongs to 

 the amaryllis family, and has been put to a 

 great variety of uses in Southern Mexico and 

 the several republics of Central America. The 

 dried flower-stems have been extensively util- 

 ized to make thatched roofs for tropical houses, 

 the strength of the fiber giving to such roofing 

 a wonderful durability. The sap of the leaves 

 of one species of the American aloe (coarser 

 than the one which is the subject of this arti- 

 cle) becomes, when fermented, the well-known 



