1869.] 



on the Scientific Exploration of the Deep Sea, 



421 



it had no contents to be retained. The principle, however, seems so good, 

 that we should hope it may be more successfully applied. 



36. The very deep dredgings in this trip yielded an abundance of novel 

 and most interesting results in every division of Invertebrata. Among the 

 Mollusca were valves of an imperforate Brachiopod, with a septum in the 

 lower valve, which we propose to name Atretia gnomon. Some shells 

 were of a considerable size ; and the fry of Isocardia cor {Kelliella abyssi- 

 cola, Sars) were not uncommon. Among the Crustacea there were 

 new species of Cumacea ; a beautiful Amphipod of a bright red colour, 

 with feathery processes of a golden colour at the tail ; with a considerable 

 variety of Isopoda, Phyllopoda, and Ostracoda, among them several forms 

 apparently new. There was also a magnificent Annelid, of a purplish hue, 

 with purplish-brown spots on the line of segmentation. Two or three young 

 specimens were here obtained, at a depth of 1215 fathoms (Station 28), of a 

 most interesting Clypeastroid, of which a mature example was afterwards 

 dredged in the Third Cruise (§ 77). These were at once recognized as be- 

 longing to an entirely new type ; but since our return we find that a form, 

 generically if not specifically the same, had been obtained by Count 

 Pourtales during his last dredgings in the Gulf of Mexico, and had 

 been described by Prof. Alex. Agassiz under the name Pourtalesia mi- 

 randa. This type is of extraordinary interest from its being the living re- 

 presentative of a very singular little group of the Ananchytidce (including the 

 genus Infulaster, D'Orb., to which it seems most closely allied), which 

 are specially characteristic of the newer Chalk. In the 1443 fathoms' dredg- 

 ing (Station 20) a Holothurian was obtained 5 inches long and 2\ inches in 

 circumference. Several very fine Corals were obtained during the Rockall 

 trip ; among them magnificent examples of Lophohelia prolifera and 

 Caryophyllia Smithii. The Foraminifera, as before, were remarkable for 

 their size, the same types being generally predominant. But specimens 

 were here obtained for the first time of a peculiarly interesting Orbitolite, 

 a type not hitherto discovered further north than the Mediterranean, and 

 there attaining a comparatively small size. Perfect specimens of this Orbi- 

 tolite must have a diameter of a sixpence ; but owing to its extreme 

 tenuity, and to the facility with which the rings separate from each other, 

 no large specimens were obtained unbroken, though it was evident that 

 their fracture had taken place in the process of collection. No greater 

 proof can be adduced of the extreme stillness of the bottom at great 

 depths, than is afforded by the extraordinary delicacy of these disks, which 

 are so fragile as to be with difficulty mounted for observation. Their plan 

 of growth corresponds with that of the " simple type" of this genus, all 

 the " chamberlets " being on the same plane ; but the form of the cham- 

 berlets corresponds with that of the chamberlets of the superficial layers 

 of the "complex type" *. It is a fact of peculiar significance that instead 



* See Dr. Carpenter's " Researches on the Foraminifera," Part I., in the Philosophical 



