PHYSIOLOGY. 



763 



moved, a nodule of new formed splenic tissue 

 was formed, inclosing in its substance foreign 

 bodies that could only have been introduced 

 through the wound at the time of the opera- 

 tion. Apart from some embryonic tissue, the 

 nodule in microscopic character was almost 

 identical with normal spleen. Among the other 

 conditions found, the most noteworthy were the 

 new formation of adenoid tissue and the trans- 

 formation of the parenchyma of lymphatic 

 glands into splenic tissue. This last circum- 

 stance supports the view held for some time 

 by Prof. Eternod that the spleen is only a vast 

 elaborated lymphatic gland. 



Dr. Alfred Baring Garrod has made a series 

 of experiments to determine the place of ori- 

 gin of uric acid in the animal body, and par- 

 ticularly which of the two hypotheses is cor- 

 rect : that it is first present in the blood and 

 is then secreted from the blood by the kidneys ; 

 or whether it is formed by the kidneys them- 

 selves. By the method he devised, he was 

 able to discover the presence of uric acid in 

 minute quantities of blood. From the results 

 of his investigations, he draws the conclusion 

 that every argument is in favor of the hypoth- 

 esis that uric acid is formed by the kidney cells 

 in the form of ammonium urate, and that the 

 traces of sodium urate found in the blood are 

 the result of a necessary absorption slight in 

 amount of the ammonium urate from the kid- 

 neys into the blood, and its subsequent con- 

 version in that fluid into sodium urate. 



Reproduction. In his work on the "Physi- 

 ology of the Embryo," Dr. W. Preyer has pre- 

 sented the results of the investigations in this 

 branch of physiology from the time of Aris- 

 totle down. The matter of the work is largely 

 drawn from observations on the common chick, 

 but other animals mammalia, reptiles, and 

 fishes have been drawn upon for information ; 

 and the most valuable observations recorded 

 are those on the Guinea-pig, dog, etc. The 

 author laments the scarcity of material and of 

 opportunities for investigation on the human 

 subject ; and recommends that in foundling hos- 

 pitals and lying-in institutions a supply of ap- 

 paratus should be kept ready for observing the 

 physiology and pathology of the new-born, 

 since much may be learned from the phenome- 

 na which occur within the first minutes or hours 

 after birth. It is shown that in the chick 

 the primitive blood, or haBmolymph, begins to 

 move before the occurrence of the first heart- 

 beat. Important results are recorded of ex- 

 periments connected with the effect of tem- 

 perature and of chemical agents on the embryo, 

 which, considered together with these relating 

 to the diffusion of substances between mother 

 and fetus, have a practical bearing on the 

 medical use of the various drugs during preg- 

 nancy. In certain experiments, the coagula- 

 tion of blood from the embryo was observed 

 to be very slow. Other experiments show 

 that some of the digestive fluids are early in 

 appearance and activity, while the amylolytic 



faculty is acquired at a comparatively late pe- 

 riod. Spontaneous movements of the embryo 

 take place long before its maturity ; and Prof. 

 Preyer considers that muscular action occurs 

 earlier than is commonly supposed. 



The generally received theory that the " cor- 

 pus luteum is the effect of pregnancy alone," 

 and is therefore an infallible sign of the preg- 

 nancy, has been shaken by more recent inves- 

 tigations. Arthur Farre and other observers 

 have shown that, whether the ovum is fecun- 

 dated or not, the corresponding Graafian folli- 

 cle presents after its rupture certain determi- 

 nate characters which collectively negative the 

 conclusion cited above and which was arrived 

 at by Haller. The initial stages of develop- 

 ment in the corpus luteum of ovulation and in 

 that of pregnancy are essentially the same; 

 but the history of the corpus luteum of ovula- 

 tion is played out in about two months, while 

 that of pregnancy extends over a period of thir- 

 teen or fourteen months. 



Action of Poisons. Dr. H. C. Wood, of Phila- 

 delphia, has published a series of observations 

 on the physiological action of hyoscine, one of 

 the two active principles contained in henbane. 

 It is an alkaloid yielding crystallizable salts. 

 He generally used the hydrobromate, but occa- 

 sionally the bydriodates. Frogs were found to 

 be sensibly affected by y^- their weight of 

 hyoscine, but at least ^ was necessary to 

 produce a toxic action. The symptoms are 

 very uniform, and consist of an increasing slug- 

 gishness, with a progressive loss of voluntary 

 movement and a corresponding depression of 

 the reflex activity, bnt without marked loss of 

 sensibility. Death is brought about by failure 

 of breathing, while the heart beats for a con- 

 siderable time after arrest of respiration. The 

 alkaloid therefore acts as a motor-spinal de- 

 pressant; as a centric respiratory depressant, 

 causing death by asphyxia. It has very little 

 effect on the circulation, what influence it does 

 exert being in the normal animal set aside by 

 the asphyxia it produces. It does not paralyze 

 the pneumogastrics, but in enormous doses 

 paralyzes the vaso-motor system. On the heart 

 itself its influence is feebly depressant. One 

 hundredth of a grain injected hypodermically 

 into the human subject always produced well- 

 marked constitutional effects. The symptoms 

 usually came on in about ten minutes, and con- 

 sisted of dizziness, impairment of vision, dry- 

 ness of the mouth, and an inability to walk 

 straight. In many instances this was followed 

 by deep sleep, lasting for many hours. 



M. Lacerda, who is investigating the prop- 

 erties of the poison of serpents, has ascertained 

 that the venom of the Hachesis rhambeata has 

 the power of digesting albuminous substances, 

 and of emulsifying fats. A piece of beef 

 chopped and put in a solution of the poison 

 immediately became pale and loose, and, after 

 being kept for sixteen hours at a temperature 

 at no time of more than 84, was broken up 

 into a greenish liquid. Coagulated egg-albu- 



