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NATURALIST'S GUIDE TO THE AMERICAS 



peared. On April 2 many small grayish 

 moths were seen in the woods. On 

 April 17 a mourning-cloak butterfly 

 (Euvanessa) was seen. By April 18 the 

 snow had nearly disappeared from the 

 fields. Mosquitoes (Culex annulatus) 

 first appeared on April 20, and were 

 biting on April 24, but did not become 

 troublesome until over a month later. 

 The sap of the white birches began to 

 flow freely on April 20. On April 23 a 

 small space of open water was seen near 

 the mouth of the Liard. Frogs (Rana 

 cantabrigensis latiremis) were first ob- 

 served on April 28. 



On April 29 Liard River broke up. Its 

 advancing flood first opened a channel 

 nearly straight across the Mackenzie, 

 forcing the ice with irresistible power 

 up on the opposite bank in immense 

 piles. At the same time a mound 60 

 or 70 ft. in height was formed at the 

 mouth of one of the channels of the 

 Liard, several immense cracks opened 

 in the white expanse before the post, 

 and the huge sheets were soon broken 

 up. The stupendous amount of force 

 exerted by the river upon the broad 

 expanse of ice, 5 ft. in thickness, as with 

 a grinding roar it folds and crushes the 

 mighty sheets like cardboard, reducing 

 them to powder and forcing them aloft 

 in great mounds, impresses the beholder, 

 who is likewise occupied in considering 

 the possibility of the river being dammed 

 sufficiently to overflow the ground on 

 which he stands. Such a catastrophe 

 has destroyed more than one post on 

 the Mackenzie in years past. 



At this time a few ducks appeared in 

 open places on the river. On May 6 a 

 small quantity of snow fell. The leaves 

 of Ribes oxyacanthoides began to appear 

 on May 8. By this time the river was 

 nearly clear of ice below the mouth of 

 the Liard, but above its mouth the ice 

 in the Mackenzie was still intact. On 

 May 10 large sheets of the Mackenzie 

 ice broke away and floated down, but 

 the river did not open from above until 

 May 13. The water then rose and 

 became filled with ice, but on the fol- 

 lowing day was nearly clear again and 



had fallen. On May 10 the leaves on 

 aspens and birches were half an inch in 

 length. About the middle of May blue 

 violets (Viola albertina) blossomed. 

 The weather continued warm and vege- 

 tation advanced steadily. On May 18 

 Virburnum pauciflorum and Populus 

 balsamifera put forth their leaves, 

 and mountain cranberry (Vitisidaea) 

 was in flower. Birds were now coming 

 fast and additional species were noted 

 daily, but on May 21 the weather turned 

 cold and stormy. This had the effect 

 of retarding the advance of vegetation 

 and the tide of bird migration. On May 

 22 Ribes oxycanthoides and Calypso 

 bulbosa were in flower. The weather 

 remained cold and stormy during the 

 remainder of the month and the condi- 

 tions of vegetation and of bird migration 

 remained almost at a standstill. On 

 May 29 several inches of snow fell. 



Mackenzie below Fort Simpson: On 

 June 1, 1904, 1 left Fort Simpson, and 

 spent the remainder of the month de- 

 scending the Mackenzie, my rate of 

 travel keeping pace in general with the 

 advance of spring. The weather during 

 the first few days of June was favorable 

 and vegetation made good progess. 

 On June 2, a few miles below Fort Simp- 

 son, the leaves of the tamaracks were 

 just coming out. All along the river 

 more or less ice still lay on the banks, 

 but a few miles above Fort -Norman 

 the quantity was astounding. Many of 

 the stranded cakes were upward of 20 

 ft. in thickness. On June 17, below 

 Fort Norman, a small quantity of snow 

 fell. On June 21, at Fort Good Hope, 

 the leaves on most of the trees were 

 about half grown. On the same date 

 the sun was visible at midnight from a 

 low hill near the post, and many birds 

 were in full song at that hour. For 

 the next three weeks, north of this 

 point, the sun was continually above 

 the horizon. Vegetation now advanced 

 rather faster than our rate of travel 

 northward, but was not at its height 

 when we reached the delta of the Mac- 

 kenzie on June 30. 



Preserved areas: Peel River Preserve: 



