Scientific Intelligence. — Zoology. 449 



observations respecting them to Samuel Rheen, Sir Paul 

 Ryeaut, Linnaeus, Hoegstroem, Pallas, Fabricius, and Zetter- 

 stadt. None of these authors, however, with the exception of 

 Hoegstroem, have been present to witness a migration. M. 

 Bravais and myself have been more fortunate ; and I shall 

 here give a short account of our observations. Many of the 

 members of the Northern Scientific Commission, among 

 others, MM. Gaimard and Sundevall, traversed Lapland in 

 September 1838 ; and they never fell in with a single lem- 

 ming. The following year, at the same period, we saw them 

 in myriads on the plateau of Lapland. AtBossecop (Lat. 70°) 

 they were rather scarce, and again became so when we de- 

 scended below the limit of the zone of the white birch. They 

 again became very common in the neighbourhood of Karasu- 

 ando on the banks of the Muonio, but on the right side of this 

 river, a little below Muonioniska (Lat. 67° 55'), they were 

 truly innumerable, and it was impossible to look around one 

 without seeing a great number at once, and all running in the 

 same direction parallel with the river. This, then, was the 

 commencement of the migration ; the army was on march. 

 On the plateau, on the contrary, they ran about hither and 

 thither, without inclining to any particular direction. When 

 they descended lower into the plain, their ranks became 

 closer. Linnaeus says, " They trace rectilinear parallel fur- 

 rows, from two to three inches deep, and many ells distant 

 from each other. They devour every thing in their passage, 

 plants and roots, and nothing turns them aside from their 

 course. If a man stand in their way, they slip between 

 his legs. If they meet with a rick of hay, they gnaw 

 their way through it, and pass along. If a rock oppose 

 their progress, they run round it, and resume their rectilinear 

 course. When a lake occurs on their route they cross it in a 

 right line, whatever may be its breadth, and that, very often 

 at its greatest diameter. Should a boat be lying in the line of 

 their passage, they creep over it, and again throw themselves 

 into the water on the other side. Even a rapid river cannot 

 arrest them ; they throw themselves into the current, although 

 they should all perish in it." All these details are confirmed 

 by others, and wc are assured that in 1833 they ascended in 

 the boats as far as Dupvig, near Bossecop, and to llernoesand 



