xxiv.] NO UNITY OF PLAN 227 



An anecdote will show how persistent and skilful he 

 was, when he wanted a rare and valuable specimen. 

 Among the few specimens I had kept from my numer- 

 ous geological explorations was the head of a mammifer 

 of the Miocene from Nebraska, showing the brain, with 

 even a little reddish colour of the animal's blood on it. 

 Agassiz tried two or three times to get it for his 

 Museum. I resisted, wishing to keep it as a memento 

 of my excursion in Nebraska in 1863. When on the 

 point of leaving Cambridge for a long sojourn in 

 Europe in 1864, Agassiz gave a large dinner party in 

 my honour ; and as soon as we were all seated at table, 

 in a loud voice, with an imploring tone and in the most 

 friendly way, he begged for that specimen so hard that 

 it would have seemed cruel to deny his request. In 

 fact, that day he acted like a spoiled child who wanted 

 a long-desired toy. Of course he got it. 



Agassiz's first plan was to work at living and fossil 

 fishes, an immense domain for a naturalist. He added 

 to it the fossil echinoderms and afterward the living 

 echinoderms. All the rest of his work came acciden- 

 tally or incidentally, but not as a result of a unity of 

 plan. He studied glaciers as a pastime, and to prove 

 that the theory of de Charpentier and Venetz was wrong. 

 His researches on the Mya and Trigonia were prompted 

 by Gressly's discoveries of fine and rare specimens of 

 these two families of molluscs. As soon as he arrived 

 in America, he turned to turtles and jelly-fishes, and 

 began to work on them with the help, first of Charles 

 Girard and Desor, afterward of Mills and Clark. Agas- 

 siz was too easily drawn from one study to another. 



