June 9, 1911] 



SCIENCE 



811 



to see him again. He manages to come to 

 the museum for an hour or so a day, sees a 

 few of his friends every day, and keeps 

 going just enough to be employed. He 

 improves daily, and I see no reason why 

 he should not have a long period of useful- 

 ness yet, though of course nothing like his 

 old work can now be expected from him 

 again. ..." 



In March, 1871, he writes (from Cam- 

 bridge) — "I am just getting out a new 

 edition of the Seaside Studies, which will, 

 however, be a mere reprint" — and in 

 March, 1872 : " I hope you will accept the 

 offer to go round the globe, and if you go 

 may you get all the antediluvial things 

 left. I am greatly afraid father's expedi- 

 tion is not going to result as well as we 

 hoped; the vessel is a great disappoint- 

 ment, five weeks out of ten they have spent 

 repairing. They have left Rio, and the 

 next mail trust to hear from them in the 

 Straits of Magellan." 



In April, 1872, he says: "Don't be 

 alarmed by the number of my epistles. 

 But I wanted to acknowledge at once the 

 safe arrival of the 'Calveria' and of the 

 ' Phormosoma. ' I need not tell you how 

 greatly obliged I am to you. ..." 



The "Revision of the Echini"^ began to 

 appear the year after his return from 

 Europe. This is the best known of the 

 works of Alexander Agassiz and at once 

 stamped the writer as the leading author- 

 ity on the subject. Part I. deals with the 

 literature, nomenclature, synonymy and 

 geographical distribution of the echini, 

 and extends to 242 pages. Part II. deals 

 with the echini of the east coast of the 



^"Eevision of the Echini," Illustr. Cat. Mus. 

 Comp. Zool. (Cambridge, Mass.), No. VII., 1872- 

 1874; by Alexander Agassiz. It was divided into 

 four parts for purposes of publication; Parts I. 

 and II. were issued together in 1872, the introduc- 

 tion being dated August, 1872, Part III. in Sep- 

 tember, 1873, and Part IV. in January, 1874. 



United States, including a report on the 

 deep-sea echini collected in the Straits of 

 Florida by Pourtales in 1867-1869, and 

 extends to 136 pages. Part III. contains 

 the descriptions of the species of recent 

 echini, and extends to 251 pages. Part 

 IV. deals with the structure and embryol- 

 ogy of the echini, and extends to 141 

 pages. The text thus occupies 770 quarto 

 pages, and is illustrated by seven maps 

 showing the geographical distribution and 

 87 plates giving full figures and details, in 

 addition to numerous wood-cuts in the 

 text. This report represents an immense 

 amount of work and close study, and it 

 became the standard for all subsequent 

 investigations dealing with this class of 

 animals. 



Agassiz throughout his active scientific 

 life was a constant student of echinoderms. 

 He worked on starfishes and crinoids, but 

 the principal object of his interest was the 

 recent echini. His first publication on 

 this fascinating group of animals was in 

 1863, and. his last in 1909, covering a term 

 of forty-six years, a long period of sus- 

 tained interest and work. He described a 

 considerable part of the deep-sea species 

 and genera known to science in his mono- 

 graphs on the deep-sea echini collected by 

 the Challenger, Blake and Albatross ex- 

 peditions. He described as new, about one 

 third of the known recent echini, of which 

 there are some 450 species. 



In addition to systematic work, he pub- 

 lished on the development and morphology 

 of echini as well as on their geographical 

 and bathymetrical distribution. His work 

 was almost wholly on recent forms, but in 

 several of his works, especially the revi- 

 sion, and Challenger report, there is dis- 

 cussion of, and some observations on, fos- 

 sil echini. 



The three years immediately succeeding 

 his return from Europe in December, 



