Hbdley. — Restiits of Dredging. 69 



On passing out to the open sea from the Hauraki Gulf we 

 encountered a heavy swell, and found that the gale which had 

 proved so disastrous to the Dunedin excursion had followed us 

 up the coast. The success ultimately achieved was largely 

 due to a happy suggestion of Mr. Cooper. By his advice we 

 packed a sack with cotton- waste and poured therein a couple 

 of bottles of machine-oil. Trailing this over the ship's side as 

 we drifted, a zone of calm water afforded us protection while 

 we dredged. 



The spot selected for operations was in the vicinity of 

 Cuvier Island, east of Great Barrier Island, in S. lat.36°8\ 

 E. long. 175° 55' ; depth, 110 fathoms. The time, sunrise on 

 the 22nd January. 1904. 



At or about the 100-fathom zone the submarine slope here, 

 as elsewhere in New Zealand or Bast Australia, suddenly 

 changes to a steeper descent. I have met with no explanation 

 of this phenomenon, and now venture to suggest that this 

 alteration marks the lowest point at which currents have 

 transported material.* 



After twenty minutes' winding, the bucket came up full to 

 overflowing with soft, sticky, green mud. A second haul pro- 

 duced similar results. A few echini were entangled in frayed 

 rope-yarn attached to the small end of the bucket. 



We returned to Auckland with about a third of a 

 ton of sea-bottom. Mr. Cooper hospitably gave the party 

 the use of his premises. After reserving samples for geo- 

 logical examination, the mud was placed in fine sieves, 

 on which was played the garden -hose. On preliminary 

 examination the mud, which was perhaps coloured by glau- 

 conite, showed but few shells ; washing yielded about a 

 spoonful of shells to a gallon of mud. An interesting feature 

 is the occurrence of several species, such as Poroleda lanceo- 

 lata and Loripes concinna, previously only known as Tertiary 

 fossils. 



It was resolved by the company that Mr. Suter take 

 charge of the collections and distribute different groups to 

 specialists who might undertake their study, and that types 

 of new species should be ultimately placed in the Colonial 

 Museum. 



Under this arrangement the examination of the following 

 Mollusca has been assigned to me. My labours have been 

 much lightened by the kindness of Messrs. Suter and Mur- 

 doch, who sorted out the species and assisted me with pre- 

 liminary determinations. 



* Since writing the above i find that Admiral Wharton has already 

 advanced this explanation — "Nature," 25th February, 1897, p. 392. 



