THE REVISION OF THE ECHINI 121 



" Revision of the Echini ; " fortunately about three fifths 

 of the edition of the Plates had been struck off and was 

 safely housed at the Museum. This leaves us with rather 

 a short supply, but the remainder of the book, which I 

 hoped to get out before spring, must be delayed a long 

 time, as I feel neither heart nor have I the time to start 

 fresh and do all this again just as it was completed. I 

 have sent to the Zoological Society a package for you, 

 which please claim from Mr. Sclater. I presume it should 

 arrive a few days after this letter. I have made pretty 

 extensive use of the new processes of photographic print- 

 ing in my book, and from what I have succeeded in 

 obtaining trust it will hereafter be possible to supersede 

 the old lithographic processes, which are wasteful in 

 time and money, and not half as accurate. 



The famous Challenger Expedition left England, with 

 Wyville Thomson as the naturalist in charge, in Decem- 

 ber, 1872, and by April, 1873, the ship was in Bermuda. 

 Wyville Thomson wrote Agassiz from there, asking him 

 if he could not pay them a visit in May, when they 

 touched at Halifax. 



Agassiz eagerly accepted this invitation, and ran up 

 to Halifax, where he was a guest of the Challenger for 

 a few days. The younger naturalists of the expedition 

 were all pronounced evolutionists, and as the name of 

 Agassiz conjured up to them opposition to these views, 

 there was much curiosity among them as to what sort 

 of a man Alexander Agassiz was. Sir John Murray, 

 one of the staff, in his address in memory of Agassiz, 

 speaks of the excellent impression which the young 

 naturalist made on every one, and how different they 

 found his opinions from those of his father. " He was 



