104 NATHANIEL SOUTHGATE SEALER 



for him. This was an inevitable element in his method of teach- 

 ing, and has been inevitably followed by all inquirers who have 

 taught. In this process of exploration it was his custom to set 

 one of us to work on a group of animals concerning which he 

 had some knowledge, so that he could guide his inquirer, at 

 least at the outset of his investigation. I recall that in this way 

 I began a study of the family of the conchifers known as the 

 Arcidse, including the fossil and recent trigonias. For a while I 

 felt that I was following on the trail which he had broken, and 

 then, as in the matter of the geographical and geological dis- 

 tribution of the genera and families, etc., I began to teach him 

 a bit that he did not know. He was as eager to receive as to 

 give, and what I supplied went into his memory as his own dis- 

 coveries, which in a way they were, for the direction of the work 

 came from his mind. In time, as will be noted hereafter, this 

 plan of collaborative work gave him trouble, as it has given 

 trouble to others who taught in the same way, in that good 

 old way that makes the pupil feel that he is the master and 

 thereby wins to his powers. 



At this time the relatively small community of scientific men 

 about Boston contained a much larger measure of ability than 

 it now does. Besides Agassiz, who by his wonderful personality 

 held the foremost place, there were Jeffries Wyman, Charles T. 

 Jackson, Asa Gray, William B. Rogers, William Cranch Bond, 

 Benjamin Peirce, B. A. Gould, as well as a host of lesser yet able 

 men, among whom I may name William Stimpson and later 

 Jules Marcou. The most usual meeting-place of these men, or 

 of most of them, was the Boston Society of Natural History. 

 Of this society I soon became a member, and shortly was en- 

 gaged in its then active life. Thence until about 1870, with the 

 exception of the two years and a half from the early part of 

 1862 to the autumn of 1864, this institution was much in my 

 life. At first my efforts were limited to bringing about debates 

 amongst the elders, by asking questions which were contrived 

 to accomplish the end. Our particular aim was to set Agassiz 



