1866.] LORD — MUSK-RATS AS BUILDERS. 51 



My first proceeding was to hunt carefully round the lake to 

 discover, if possible, some evidence of a burrow — not a trace of 

 such could I find ; next the rush houses underwent a rigid scrutiny. 

 In each musk-rats were living, and more than this, whole families 

 had clearly resided in the several mansions for a very long time. 

 I now felt convinced there must be two distinct species, one a 

 miner, the other a builder ; and further, that the two species had 

 been classed together by observers, under the supposition that 

 they changed quarters, in accordance with the seasons. The next 

 thing was to prove my supposition based on correct data. 



Tents were soon after struck, and the lake, with all its li vino- 

 treasures, abandoned to nature and the red man. 



We must take up our story at Fort Colville, one of the earliest 

 trading posts of the Hudson Bay Company, situated on a gravelly 

 plateau, close to the Kettle Falls, on the Columbia river, about a 

 thousand miles from the sea. 



The two weary winters passed in this solitary spot were cold 

 enough to satisfy an Esquimaux, the temperature often as low as 

 thirty and thirty-two degrees below zero, with deep snow covering 

 the ground for full six months of the twelve. Through the 

 gravelly valley leading from the Fort to the hills, wound a sluggish 

 muddy stream, with deep banks on either side, in which dwelt 

 whole colonies of musquash. About a mile and a half from the 

 stream, divided from it by a steep ridge of rocks, was a sedgy flat, 

 surrounding a deep, quiet pool, so overshadowed and shut in by a 

 brake of bulrushes, as to be hidden, until its margin, reached by 

 wading and cutting a trail through the reedy fringe, revealed its 

 water, and a city of musquash-houses scattered like hay-cocks 

 over the entire surface. 



In the bright, glowing sunshine of mid-summer, I carefully 

 watched the stream and pool, fully satisfying myself that both 

 localities were densely populated ; and, further, that < builders ' 

 and < miners ' were blessed with infant workers, born, some in the 

 rush dwellings, others in the nurseries of the mud tunnels. So 

 far so good, nothing more could be done until winter. On care- 

 fully comparing several of the musk-rats shot in the pool, with 

 those brought from Osoyoos Lake, I found them to be specifically 

 alike, but differing most markedly from the rats inhabiting the 

 Colville stream ; others procured from very distant mud banks, 

 east and west of the Cascade Mountains, tallied exactly with these 

 and each other, as did a series of rush-building-rats from widely 



