236 PROCEEDINGS OF THE ACADEMY OF [1896. 



Volumes and Surfaces of Organisms."^^ One of the last demonstra- 

 tions he made was at a meeting of the Bibliographical Club of the 

 University of Pennsylvania, when he exhibited contractile films of 

 gelatin in illustration of the mechanical conditions underlying the 

 problem of the arrangement of the convolutions of the brain. 



In January, 1890, he writes : " It is my hope to reduce the doc- 

 trine of evolution into a simple realization of Newtonian principles. 

 The three great Newtonian laws of motion are at the bottom of the 

 whole matter. Some day I shall be able to tell a great deal that I 

 have kept to myself in order to test its truth. * * * * lam 

 engaged — and will be hereafter almost entirely — in determining the 

 factors and processes which have effected the evolution and diverg- 

 ence of species. * * * * I have at last worked out a new 

 theory of inheritance which must ultimately replace those of Weis- 

 mann and Darwin, or at least furnish the foundation by which the 

 data and phenomena of variation and inheritance can be co-ordi- 

 nated with the great universal principle of the doctrine of the con- 

 servation of energy. The speculations of Darwin, Haeckel, Weis- 

 mann. Brooks, DeBries, Strassburger and Nageli looking to a theory 

 of inheritance are irreconcilable with the fundamental postulates of 

 physical science, and must be abandoned. This also renders the 

 conflict between the hypothesis of Darwin and those of Lamarck one 

 of primary importance, and sharply defines the line of battle be- 

 tween the thinkers who range themselves under the banner of one 

 or the other of these prophets of transform ism." 



While it is impossible to say what Dr. Ryder would have accom- 

 plished in his attempt to use mathematics as a medium of expression 

 of biological problems, this much can be said, not only for him, but 

 for all others similarly placed, that a course of training in geometry 

 and the higher mathematics should be a part of the equipment of 

 the student in biology. It does, indeed, seem pitiable that, ascend- 

 ing the heights of knowledge, he finds, as he nears the top, that the 

 key which he believes can alone open the temple erected there has 

 been left behind. 



III. 



Dr. Ryder was five feet eleven inches high, of a slender, slightly- 

 stooping figure. While spare he had a robust physique. He was 



12 See Bibliography, Nos. 182, 184, 186, 187, 189, and especially Nos. 190, 

 191, 192, 195, 199, 200, 204, 205, 205 and 207. 



