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Annals of Medical History 



of paleontology. His discussions of the few 

 lesions he recognized were meager and in- 

 adequate. He has described a fractured 

 skull of a Pleistocene Hyaena and a frac- 

 tured femur of Anoplotheriwn. 



Paleontology lends considerable light to 

 the study of the antiquity of disease. The 

 study of the lesions so far known among 

 fossil animals indicates nothing new in the 

 nature of pathological processes but simply 

 extends our knowledge of disease to a vast- 

 ly earlier period than had previously been 

 known. It seems quite probable that some 

 of the diseases exhibited by the extinct 

 vertebrates went out of existence with the 

 race of animals which were afflicted. If this 

 proves to be true it will be an interesting 

 opportunity to study the details of lesions 

 of extinct diseases. There seems to be little 

 possibility of determining the fundamental 

 cause of disease other than is already known; 

 for disease is apparently one of the mani- 

 festations of life, and has followed the same 

 lines of evolution as have plants and ani- 

 mals, and is possibly directed by the same 

 factors. Such a study as the present may, 

 however, throw light on the origin of many 

 of the diseases to which the human race is 

 a prey. A knowledge of the pathological 

 processes which have taken place in animals 

 of geological antiquity will aid in an un- 

 derstanding of the general nature of disease. 



The literature of vertebrate paleontology 

 contains a number of incidental references 

 to the diseased nature of the fossilized bones 

 of fishes, reptiles, birds, and mammals, the 

 lesions described indicating a variety of 

 diseases, some of which are not uncommon 

 today. It is manifestly impossible to diag- 

 nose correctly, on the basis of our modern 



13 Among diseases which have become extinct with- 

 in historical times may be mentioned the sweating 

 sickness described by Hecker in "Epidemics of the 

 Middle Ages," 1846, pp. 181-353. 



14 The soft parts of fossil vertebrates have been 

 discussed by a number of writers. Our knowledge 

 of the entire subject is reviewed in the author's 

 paper, "A New Fish Brain from the Carboniferous 



knowledge of recent diseases, all of the 

 lesions which are preserved in a fossil condi- 

 tion. In the extinction of the ancient races 

 of animals, certain diseases, without doubt, 

 became extinct with them, 13 and it is 

 partly the purpose of this paper to inaugu- 

 rate an inquiry into the nature of the dis- 

 eases of fossil vertebrates. No one has yet 

 made a study of the evidences of disease 

 among fossil animals, since these conditions, 

 whenever noted, have been referred to only 

 in an incidental way, by writers on paleon- 

 tological subjects. 



Geological evidences of the diseased state 

 of animals are necessarily restricted to path- 

 ological lesions on the hard parts of fossil 

 animal remains. Soft parts 14 are seldom 

 fossilized, and the few specimens known 

 have not been subject to disease. Since the 

 pathological changes which affect the hard 

 parts of animals today are relatively few 

 when compared to the diseases which aillict 

 the body as a whole, it is to be supposed 

 that the paleontological evidences of disease 

 are but partial indications of the prevalence 

 of pathological conditions in geological time. 

 The following account, too, must be read in 

 the light of the paucity of evidence available 

 for discussion. The details are meager, but 

 since they are all we have, they may be 

 deemed worthy of consideration. 



It will be clearly evident, after a consid- 

 eration of geological matters, that all paleon- 

 tological evidence is of relative value, since 

 such small portions of the ancient faunas 

 and flora are preserved in the rocks. How- 

 ever, we are safe in stating, from such 

 evidence as we have, the probabilities of the 

 occurrence of numerous diseases among ex- 

 tinct animals, just as it is safe for us to 

 state, on the basis of a single tooth in a 



of Kansas, with a Review of Other Fossil Brains," 

 J. Comp. Neurol., April, 1915, vol. 25, No. 2, 

 where an annotated bibliography of fifty papers 

 will enable the interested reader to see just how 

 meager is our knowledge of the soft parts of extinct 

 vertebrates. Many of the softer structures are 

 represented by impressions on the stone. 



