1874.] On Dredgings and Deep-sea Soundings. 423 



XII. " On Dredgings and Deep-sea Soundings in the South At- 

 lantic, in a Letter to Admiral RICHARDS, C.B., F.R.S." By 

 Prof. WYVILLE THOMSON, LL.D., F.R.S., Director of the 

 Civilian Staff on board H.M.S. ' Challenger.' Received 

 May 25, 1874. 



Melbourne, March 17, 1874. 



DEAK ADMIRAL BICHABDS, 1 have the pleasure of informing you 

 that, during our voyage from the Cape of Grood Hope to Australia, all 

 the necessary observations in matters bearing upon my department have 

 been made most successfully at nineteen principal stations, suitably 

 distributed over the track, and including Marion Island, the neighbour- 

 hood of the Crozets, Kerguelen Island, and the Heard group. 



After leaving the Cape several dredgings were taken a little to the 

 southward, at depths from 100 to 150 fathoms. Animal life was very 

 abundant ; and the result was remarkable in this respect, that the general 

 character of the fauna was very similar to that of the North Atlantic, 

 many of the species even being identical with those on the coasts of Great 

 Britain and Norway. The first day's dredging was in 1900 fathoms, 

 125 miles to the south-westward of Cape Agulhas; it was not very 

 successful. 



Marion Island was visited for a few hours, and a considerable collec- 

 tion of plants, including nine flowering species, was made by Mr. Mose- 

 ley. These, along with collections from Kerguelen Island and from 

 Yong Island, of the Heard group, are sent home with Mr. Moseley's 

 notes, for Dr. Hooker's information. 



A shallow-water dredging near Marion Island gaA r e a large number of 

 species, again representing many of the northern types, but with a mix- 

 ture of southern forms, such as many of the characteristic southern 

 Bryozoa and the curious genus Scrolls among Crustaceans. Off Prince 

 Edward's Island, the dredge brought up many large and striking speci- 

 mens of one or two species of Alcyonarian zoophytes, allied to Mopsect 

 and Isis. 



The trawl was put down in 1375 fathoms on the 29th December, and 

 in 1600 fathoms on the 30th, between Prince Edward's Island and the 

 Crozets. The number of species taken in these two hauls was very large ; 

 many of them belonged to especially interesting genera, and many 

 were new to science. I may mention that there occurred, with others, the 

 well-known genera Euplectella, Hyalonema, Umbellularia, and Flabellum ; 

 two entirely new genera of stalked Crinoids belonging to the Apio- 

 crinidse ; Pourtalesia ; several Spatangoids new to science (allied to the 

 extinct genus Ananchytes} ; jSalenia ; several remarkable Crustaceans ; and 

 a few fish. 



"We were unfortunately unable to laud oil Possession Island on account 



TOL. XXII. 2 K 



