228 PROCEEDINGS OF THE ACADEMY OF [1896. 



officer of the Commission to which he had been originally attached 

 as an expert. He " merited the confidence and esteem of every one 

 from the Commissioner to the humblest attendant." 



On the occasion of his resignation, 1886, Prof. Baird expressed 

 hiin.self in a personal letter in these words : " In view of the many 

 years of your connection with the Fish Commission, and the valu- 

 able services which you have rendered by the exercise of your pro- 

 fessional skill and ability, I accept your resignation with very 

 great regret." His work, however, on the Commission, did not at 

 once cease. He was employed in May and June, 1888, to investi- 

 gate the sturgeon fisheries in the Delaware River.^ During the 

 remainder of the summer of the same year, he had charge of the 

 station at Wood's Hole. 



His interest in the study of Cetacea began -while on the Commis- 

 sion. Although his work on this subject was never extensive, per- 

 haps no other group of observations better illustrate the higher 

 characteristics of his mind. 



In 1886, it was determined by the authorities of the University of 

 Pennsylvania, at the suggestion of Prof. Horace Jayne, to found a 

 chair of Comparative Histology and Embryology. As stated by 

 Prof. Jayne, " It was seen that a course was needed which would 

 give students a thorough knowledge of comparative microscopic 

 anatomy, together with the development of the tissues and of the 

 different kinds of animal forms.'"' The chair was offered to Dr. 

 Ryder and accepted, though '' he hesitated at first," to again quote 

 Prof. Jayne, " because he mistrusted his power to teach and handle 

 large classes of students, a mistrust which was never shared by his 

 friends." In many respects, the change from the duties of a bio- 

 logical expert on the Fish Commission to those of a professorial 

 position was beneficial. He was now enabled to systematize bis 

 time, and permitted to extend the range of his inquiries. By re- 

 newal of associations at the Academy of Natural Sciences, he was 

 assisted also in keeping thoroughly in touch with the progress of his 

 favorite science. 



In illustration of the zeal with which he prepared himself for his 

 new duties, the following extract is taken from a letter written to 

 Mr. Seal, from Chambersburg. " I am embracing an opportunity 

 for the collection of embryos of warm-blooded vertebrates, which I 



^Report of Fish Commission, Bulletin, 1888, p. 231. 

 * Memorial Pamphlet. 



