424 Dr. E. P. Wright on Deep-sea Dredging, 



nothing — a zone commencing at 300-fathoms mark down to a 

 depth at present quite unknown — a zone in which we now find 

 a very peculiar fauna — one into which some of the fourth-zone 

 animals may wander, but which is still wonderfully well cha- 

 racterized by its own corals and echinoderms, its vitreous 

 spongeSj and even its own peculiar fishes. Up to the present 

 I know of no published account of dredging in this zone, ex- 

 cept the very interesting paper of Mr. L. F. de Pourtales, As- 

 sistant to the United States Coast Survey (for a copy of which 

 I am indebted to the author). The field selected for the re- 

 searches of Capt. Piatt, of the Coast-Survey steamer ^ Corwin,' 

 was in a section between Key West and Havana, and the 

 casts of the dredge were made at depths of 270 and 350 

 fathoms. At these depths many species of Echinoderms, Coe- 

 lenterates, and Sponges were met with ; and, most interest- 

 ing fact of all, not only were the long spicules of Hyalonema 

 dredged up, but there was also found a fragment of the sili- 

 ceous skeleton of a sponge, forming a regular network, some- 

 what like that of Euplectella^ but lacking the spines. Mr. 

 Pourtales alludes also to a number of sponges (at least a dozen 

 species) which are not yet determined, and says that some of 

 the detached spicules are remarkable for their great size, one 

 of the slender rectangulated sexradiate type of Bowerbank 

 [and doubtless belonging to a sponge of Wyville Thomson's 

 order Vitrea] was found measuring more than half an inch. 



We may hope for more information when Professor Wyville 

 Thomson and Dr. Carpenter publish an account of their expe- 

 dition to the deep-sea valleys off* the west coast of Scotland, 

 and when the results of the fourth Swedish expedition shall be 

 known. In the meanwhile I venture to give the following 

 brief notes of a deep-sea dredging-expedition off the Portuguese 

 coast near Setubal. 



I had been asked by the Council of the Royal Irish Aca- 

 demy to draw up a report on the present state of our know- 

 ledge of that strange organism Hyalonema mirahile of Gray, 

 and was naturally anxious to procure living or well preserved 

 specimens of this species. 



Professor J. V. Barboza du Bocage, of Lisbon, kindly in- 

 vited me to pay him a visit at the season for the shark-fishing 

 (in September), promising to place all the specimens of the 

 Hyalonema in the museum at Lisbon at my disposal, and to 

 give me every assistance in his power to enable me to go out 

 to the ground where the specimens of Hyalonema lusitanicum^ 

 Bocage, had been found. Accordingly, after the meeting of 

 the British Association * in August last, at Norwich, I pro- 



* A committee was appointed by the British Association, with the 



