86 



SCIENCE. 



[Vol. XIX. No. 471 



arranged and labelled for instruction as they stand, and 

 ■which shouM be rarely, if ever, disturbed. 



The following, treated in some detail, embrace the topics 

 that occur to me at this time as appropriate subjects for in- 

 struction: The study of the human brain; especially the 

 study of the mammalian and avian brains, both of the gross 

 and the minute anatomy, the localization of functions, etc. 

 The study of muscular anomalies and their homologies in 

 the normal myology of the vertebrates. The study of animal 

 locomotion and its application to the morphology of the 

 vertebrate limb, and in general the application of photo- 

 graphic methods in studying animal locomotion.' Studies 

 in craniology, especially the comparative studies of human 

 and mammalian crania. The study of osteological varia- 

 tions, with a similar application to the normal anatomy of 

 the lower animals and the beginning of morbid processes. 

 The study of nutritive processes on tissue as correlated to 

 age." 



In addition, courses of experimental morphology might be 

 essayed. Such investigation could be encouraged without 

 encroaching on the domain of physiology, as the votaries of 

 this science somewhat arbitrarily restrict- it. Indeed, much 

 of the study of animal locomotion would be experimental, as 

 vrould also be the study of protoplasm in viscid media, under 

 rotation, compression, etc. The effects of light, temperature, 

 water in motion and at rest, etc., on organization, would 

 naturally find a place. Experiments on mutilation of em- 

 bryos might also be undertaken. 



Lectures on correlation of structure, on vegetative repeti- 

 tion, on the relation existing between phyllogenetic and 

 teratological processes, could be given, as well as the study of 

 the laws of heredity, especially in attempting to answer the 

 question of the transmittal of acquired characters. 



The teeth are so responsive to the constitutional peculiari- 

 ties of the individual that their peculiarities can be seen and 

 readily detected.' The method of procuring accurate im- 

 pressions can be applied, and the plans of preserving the 

 form of teeth be easily accomplished. 



As is known to the zoologist, the parts involved in the act 

 of mastication are important in the classification of the mam- 

 malia, the slightest departure in the form, number, position, 

 and rate of development of the teeth being for the most part 

 correlated with other variations in the economy, while the 

 shapes of the lower jaw and of those portions of the skull 

 ithat afford surfaces for attachment of the masticatory mus- 

 cles are of importance. No structures of the body resemble 

 the teeth in the character of their response to morbid impres- 

 sions; no other organs are arranged in progressive series; and 

 none other than these are evolved after birth. Hence the 

 effects of disease and accidents to which the teeth are sub- 

 jected are sure to be recorded in the shapes of the crowns 

 and roots. 



If the student of heredity were to have placed at his dis- 

 posal a collection of the casts of the permanent teeth of three 



• Instantaneous photographs have given us definite conceptions of the be- 

 havior of the manus and pes in tei-restrial and aerial movements. I had the 

 honor to point out as a result of a study of the negatives taken by Mr. E Muy- 

 bridge under the auspices of the University of Pennsylvania, that the ground 

 Is touched by the outer border of the foot and is left by the inner border, and 

 that the impact represented by this transition is expressed by an oblique line 

 that extends from without Inward (ecto-entad) across the metapodium. Pro- 

 fessor H. F. Osborne, by studying the carpus and tarsus in extinct forms of 

 mammalian life, has found that this conclusioa is of value in studying the 

 evolution of the parts. From this we can conclude that, as aresult of a plaoto 

 graphic plant in connection with advanced anatomical work, discoveries could 

 with some confidence be anticipated. 



2 This would form a morphological study on the nature of age; and would 

 more piriicularly embrace a consideration of the immature and senile forms 

 as compared with the typically adult, as well as the retention of juvenile char- 

 aoters in the adult. 



generations — that is to say, of the parent of the subject, the 

 subject himself, and the children of the subject — and if a 

 clinical history were secured of the diseases and accidents that 

 these persons had incurred, a- tenable argument might be es- 

 tablished as to the significance of the contrasts or resem- 

 blances in the forms of the teeth. 



Thus, if three generations were expressed by the letters A, 

 B, C, and if B is the subject of an acquired character (let us 

 say from scarlet fever or measles), the new form o*^ structure 

 seen in the second and third molars may be transmitted to 

 C But in order to prove this it is necessary to know the 

 peculiarities of these teeth in A. Hence, the teeth of the 

 ancestors and descendants of the person who exhibits the 

 acquired character must be known. A somewhat similar 

 plan of observation could be made on the teeth of the lower 

 animals. It is strange that those teeth with endless pulps, 

 in which growth is rapid and interference with their rela- 

 tions causes permanent records to be made in malformation, 

 should not have been used in studies of nutrition. 



In connection with myological studies a number of minor 

 problems suggest themselves; such, for example, is the na- 

 ture of white and red muscles. It has been noted that in 

 ostriches that have been confined in zoological gardens the 

 muscles of the leg undergo fatty degeneration and become 

 white in color; it is also known that the pectoral muscle in 

 many of the gallinse is white, presumably from the fact that 

 they are used but for short and infrequent flights. How 

 evident is the conclusion that a systematic study of all mus- 

 cles of active birds living in enforced confinement, as com- 

 pared with the relatively active muscles in feral forms, 

 might be undertaken with a fair prospect of throwing light 

 upon the nature of the process, and with a hope that the 

 subject of fatty degeneration (even if by this method not 

 elucidated) may have its study placed on a broad basis by 

 subjecting its tenets to the tests of systematized experiment 

 and observation ! 



The morphological study of the results of diseased action 

 might also be undertaken. The differences that obtain be- 

 tween normal individuals and those the subjects of heredi- 

 tary disease must be of importance to the anatomist and the 

 pathologist. 



The variations in the forms of the bones, as found in 

 medical museums, are of a character that suggest their rela- 

 tion to inherited causes. Every clinical observer has noted 

 the peculiar shape of the chest in families in which pulmo- 

 nary phthisis is hereditary, even though the special tubercu- 

 lous deposits are absent in some of its members. The club- 

 bling of the finger-nails is a sign of the same disposition. 

 Some writers, indeed, claim that in this class of subjects a 

 special arrangement of the fibres of the pneumogastric nerve 

 exists. Are these and similar morphological characters sus- 

 ceptible of being also gathered so as to contribute to the dis- 

 cussion of the transmission of acquired characters? Are not 

 opportunities here presented for the medically trained biolo- 

 gist to study the subject of heredity in a line so important 

 and, alas! with material so abundant? Other hereditary 

 diseases, such as struma, syphilis, and gout, are less strongly 

 marked than is the tuberculous, but even on this obscure 

 horizon landmarks are detected that are of sufficient definite- 

 ness to guide the observer to well-defined plans of study. 

 The animals of zoological gardens exhibit examples of ac- 

 quired struma, the effects of which more especially distin- 

 guish the skeleton. Can any of these characteristics be 

 transmitted? How would the skeleton of a tiger, let us say, 

 born in captivity in the third and forth generation differ 



