2 THE VOYAGE OF H.M.S. CHALLENGER. 



This pleasant arrangement for joint research was, however, frustrated by the illness 

 and death of Sir Wyville Thomson. I had, accordingly, to lay aside the whole work for 

 a prolonged period, till, in March 1882, Mr. John Murray asked me to undertake the 

 complete investigation of the Challenger Hexactiuellida, and for this purpose, in the first 

 instance, personally to undertake the separation of the latter from the rich collection of 

 Sponges obtained during the expedition and preserved in Edinburgh. Having com- 

 pleted this in April of the same year, I received, in June, most of the Hexactinellida 

 collected by the Challenger Expedition, which were forwarded to me at Graz in a well- 

 packed condition. Subsequently, at my request, a few additional Hexactinellida, which 

 were collected before by Sir Wyville Thomson and Mr. John Murray in the eastern part of 

 the Atlantic, during the expeditions of the " Lightning," " Porcupine," " Knight Errant," 

 and " Triton," were handed over to me for purjDoses of comparison, and also a number 

 of microscopic preparations which had been made by Sir Wyville Thomson. 



My material was afterwards very agreeably increased by the acquisition of a not 

 unimportant collection of Hexactinellida, partly dry and partly preserved in alcohol, 

 which Dr. Doderlein, Director of the Zoological Museum in Strassburg, had accumulated 

 during a prolonged stay in Japan, partly as the result of his own collecting on the 

 small island of Enoshima. This collection he very kindly placed at my disposal for 

 investigation. 



At my request the Challenger Commission agreed that I should include this valuable 

 material in my work on the Challenger Hexactinellida, and approved of what thus 

 necessarily involved an increase of plates. I therefore accepted the offer of Dr. 

 Doderlein, and that all the more willingly since the increase of material considerably 

 facilitated the systematic work. On the other hand, I was enabled to compare minutely 

 a collection zealously and systematically made for several years from a definite locality 

 remarkably rich in Hexactinellida, with that collected in the same locality by the 

 Challenger Expedition. 



As to the ways and means of acquiring this collection, which consisted of about 

 twenty-five dried forms and three bottles of preserved specimens, Dr. Doderlein 

 communicated to me the following notes : — " With the exception of a Euj)lectella 

 (pweni) from Simonoseki on Kiushiu, the whole collection was gathered in Sagami 

 Bay, near Enoshima. Most of the dried specimens were obtained from a shop in 

 Enoshima, where they were collected for me by the owner. The three glasses with 

 spirit contain specimens which I myself obtained with a trawling apparatus from depths 

 varying from 80 to 240 fathoms, between Enoshima and Misaki. A few dead specimens 

 which I obtained there have been sent dry. I have added a single specimen of 

 Hyalonema (sieboldii) in which the sponge body is magnificently developed, but it is by 

 no means the largest specimen which I brought with me." 



Professor Oscar Schmidt of Sti'assburg was kind enough to hand over to me, for 



