754 



PHYSIOLOGY. 



Literature. The books of the year include 

 " Manual of Practical Pharmaceutical Assay- 

 ing," by Dr. A. B. Lyons (Detroit) ; " Chemi- 

 cal Lecture Notes," by H. M. Whelpley (St. 

 Louis); "Compend of Pharmacy," by F. E. 

 Stewart (Philadelphia); and new editions of 

 Beasley's " Druggists' General Receipt-Book," 

 and Beasley's " Pocket Formulary and Synop- 

 sis of the British and Foreign Pharmaco- 

 poeias " (Philadelphia). In January, " The Chi- 

 cago Pharmacist" was discontinued, being 

 merged into "The Western Druggist," of 

 Chicago. " The American Drug - Trade " is 

 the name of a journal started in Chicago 

 with the beginning of the year. 



PHYSIOLOGY, fn a recent discussion of the 

 true aim of physiology, Prof. W. Preyer in- 

 sists upon function as the paramount object 

 of study. Physiological inquiry, he says, must 

 attach more importance to the conception of 

 evolution. Morphology has gained so much 

 from applying the method of evolution in all 

 its departments, that it is surprising that in 

 physiology, or the science of the functions, it 

 has not been applied at all, or only occasion- 

 ally and reluctantly. The neglect is due part- 

 ly to the erroneous opinion that not the physi- 

 ological function, but only its substratum, the 

 bodily organ, is capable of evolution. It is, 

 however, function that determines the final 

 form during phylogenetic evolution, and with 

 its appearance begins the differentiation of the 

 substratum of primitive beings. It is not the 

 organ from which function derives its origin, 

 but just the reverse. The functions create their 

 organs, or, to use a better definition, necessity 

 determines the organic form, which hence be- 

 comes hereditary, and ultimately in the em- 

 bryo of the higher animals in structure, at 

 least, precedes function. This is illustrated in 

 an experiment on the embryo of the land sala- 

 mander, which, when many months previous 

 to the normal time of its entry into the world, 

 if taken out of the egg and kept in water well 

 supplied with oxygen and amply fed with small 

 living water-animals, will undergo a change in 

 its organism. It has to inhale the oxygen dis- 

 solved in the water, not that of the atmos- 

 phere, like its parents breathing with lungs. 

 Its lungs, therefore, remain undeveloped, but 

 by way of compensation strong gills appear 

 at each side of the head. The originally very 

 feeble function of respiration through gills, in 

 conformity with the increased demands of the 

 growing body, creates a new organ, or calls 

 forth one possessed by its remote ancestors. 

 The animal, moreover, feels the necessity to 

 swim, not to creep, like its terrestrial parents. 

 Its four extremities, therefore, become mere 

 rudimentary appendages, while, on the other 

 hand, a vigorous rudder -tail develops. The 

 function of swimming calls forth fins, new 

 organs which the parents lack. Thus a sub- 

 stantially new animal is produced which else- 

 where does not exist, and which shows how, 

 through the development of new functions, 



new organs are formed, or, as it were, resus- 

 citated. The principle applies not only to 

 particular cases with artificially created con- 

 ditions, but to all functions. All of them pre- 

 cede the organs devoted to their exclusive 

 service. All of them originate through com- 

 petition for the necessities of life. At first a 

 simple want is easily satisfied by simple means, 

 but gradually the organism is called upon to 

 meet numerous demands requiring complex 

 contrivances through differentiation. " No or- 

 ganic structure develops without having an 

 activity, a necessity to intensify this activity 

 for its cause. The cause of this increase in 

 activity or differentiation is simply functional 

 evolution. It is the principle of all organic 

 growth, of all morphological evolution, and, 

 wherever it decreases or ceases, the latter at 

 once retrogrades. Without function, no or- 

 ganic evolution; increase of function, organic 

 differentiation; cessation of function, organic 

 retrogression." 



Nervous System. Dr. von Monakow has com- 

 municated to the Physiological Society of Ber- 

 lin an account of his anatomical investigations 

 of the brain, which related to the central origin 

 of the optic nerve. He had enucleated on one 

 or both sides the bulbus in young rabbits and 

 cats, and, after an interval of some months, 

 had examined the changes which resulted. In 

 each case he found regular ascending atrophy, 

 capable of being traced up to the origin of the 

 nerves. By this means he had been able to 

 recognize as central original spots of the nervi 

 optici, the corpus geniculatum externum, the 

 pulvinar, and the anterior corpora quadrigemi- 

 na. The corpus geniculatum and the pulvinar 

 consisted of large multipolar cells, between 

 which lay a gray medullary substance, which, 

 on being colored with carmine, showed a par- 

 ticularly strong tinge. After the enucleation, 

 atrophy of the gray medullary substance was 

 observed in both, while the cells remained al- 

 together intact. On coloring with carmine, 

 the somewhat shrunken organs appeared much 

 paler than in the normal state. In the corpo- 

 ra quadrigemina five different layers of small 

 and large cells and fibrous bands were distin- 

 guished. Of these the three innermost layers 

 lying toward the ventricle remained intact, 

 while the two external cellular layers were 

 atrophied or were altogether wanting. The 

 degeneration and disturbance of growth after 

 enucleation of the bulbus had not, however, 

 extended beyond these primary centers of the 

 optic nerve. Dr. von Monakow had, further- 

 more, removed particular parts of the cerebral 

 cortex lying within Munk's sphere of vision, 

 and the degeneration and atrophy which suc- 

 ceeded this injury, and, extended peripheri- 

 cally, could be followed through Gratiolet's 

 fibers on to the three centers of optic nerves 

 above mentioned, the corpus geniculatum ex- 

 ternum, the pulvinar, and the anterior corpora 

 quadrigemina, and beyond these centers as far 

 as the tractus opticus and the optic nerves. It 



