1853.] SUTHERLAND — ARCTIC REGIONS. 311 



agents. At the confluence of two opposite currents the largest 

 amount of foreign matter will be deposited, for there icebergs and 

 coast-ice are brought to a stand in the eddies, and are liable to be 

 detained until they are dissolved. In such cases submarine ridges 

 and mounds begin to grow above the general level of the sea-bottom, 

 and they may continue to increase until the surface of the water is 

 reached. 



A bank in latitude 67° and 68° off the coast of West Greenland, 

 well known to the whaling and cod-fishing vessels by the name 

 " Reefkoll or Riscoll Bank," seems to answer this description. The 

 depth of water on the highest part of it does not exceed fifteen fathoms. 

 It appears to be composed of angular fragments of rock and other 

 materials brought down by icebergs and coast-ice. This, however, 

 can only be inferred from the sounding line, and from the rough 

 usage to which the lines of the whalers are submitted when they 

 attack and get fast to their prey in its neighbourhood. Its limits 

 can be defined almost at all times by the clusters and groups of small 

 icebergs that take the ground upon it ; and like other banks of a 

 similar character but less extensive on the same coast, it is exceed- 

 ingly fertile in shoals of cod-fish and halibut which frequent it in the 

 months of May, June, July, and August. These and other fishes^ 

 including myriads of sharks, may pass the whole year upon it ; but 

 this we have not as yet had the means of putting to the test. 



In other parts of Baffin's Bay and Davis' Straits the bottom is 

 composed of fine mud, sand, rounded and angular fragments of rock, 

 shells, and marly deposits resulting from minute subdivision of cal- 

 careous, phosphatic, and siliceous animal and vegetable matter, all of 

 which have been brought up in the dredge. In the neighbourhood 

 of islands composed of crystalline rocks the bottom was often found 

 to be rocky ; but, as might be expected, numerous depressions were 

 filled with sand and shells. From a depth of twenty-five to thirty 

 fathoms at the Hunde Islands, South-east Bay, lat. 68°, the dredge 

 passed over a loose and softish deposit, and brought up a quantity 

 of dark-coloured rather finely divided matter resembling peat, which 

 appeared to have been the result of the decomposition of fuci at the 

 bottom. In some cases the roots, being the hardest and most en- 

 during parts, could be detected. 



Organic Remains deposited in the Arctic Seas. — Diatomacese are 

 exceedingly abundant within the Arctic Circle. Mud from almost 

 every locality has not failed to yield considerable varieties ; but the 

 most productive source is the surface-ice when undergoing decay. 

 It often occurred to me that these microscopic forms may be accu- 

 mulating in a state of great purity, and to a considerable extent, 

 in some of the highly favourable localities so common in Davis' 

 Straits. In many of the sheltered bays, where the water is still and 

 the ice dissolves without drifting much about, a brownish slime, con- 

 sisting of nothing but these forms, occupies the whole surface of the 

 water among the ice, which, after the latter has all disappeared, be- 

 comes rolled into rounded pellets by the ripphng of the water, and 



