\6] ' FRESHWATER FISHERIES OF ICELAND. 325 



Below Bruarfos tbe Ivalvliekja flows into the Laxa, close to the old 

 ford. Here there are extensive spawning places of salmon, as there are 

 numerous banks formed by broken pieces of lava. As bridges have 

 recently been built there is no necessity for using the ford during the 

 spawning season (about from September 15 to November 15), and there 

 is consequently no occasion to disturb the salmon during the spawning 

 process. It would be better if the ford was used onlj^ from May till the 

 middle of September. 



On the right bank of the Lax4 I visited the springs of a stream which 

 flows into the Laxa, and which is said to contain numerous young fish. 

 Here I had for the first time au opportunity to make some observations 

 relative to the importance of the lava which forms the bed of many 

 Iceland streams. It has already been stated in Eggert Olafson's and 

 Bjarni Paulsen's valuable reports on Iceland that the salmon like those 

 streams whose beds are composed of lava, because it abounds in hiding- 

 places. Everywhere in Iceland the truth of this statement is borne out 

 by the facts; but possibly the porous mass of the lava-bottom, together 

 with the rapid current, is apt to form suitable hiding-places for the 

 small animals which form the food of the young fish, while at the same 

 time streams with water which is not too cold will form an attraction, 

 when during winter there are cold snow-water and ice in the open river. 



The vegetation in the Lax4 is found to be very rich, showing many 

 confervae and plants of a higher order. In many places fishing becomes 

 exceedingly difticulr, because the hook or the artificial fish becomes 

 entangled among the plants, where there are many places in which 

 snails of various kinds, small mussels, and crustaceans can gather. I 

 have often heard the opinion expressed that the hot springs tend to make 

 the fish fat. This result is, of course, obtained only in a roundabout w^y. 

 It is the animal life i)roduced by the hot-spring water which furnishes 

 rich food for the fish that makes it possible for them to become fat. 



On the whole it must be said that there are spawning places at the 

 mouth of most of the tributaries of the Laxa below Bruarfos. These 

 tributaries are said to have much warmer water in winter than the river 

 itself, as they come from springs in clefts between the lava underneath 

 the meadows. The temperature of these springs is the same all the year 

 round. I found it to be 4° Celsius. For this reason the brooks are 

 always open in winter, and their comparatively warm water goes into 

 the spawning places, x^ear the springs of one of these brooks, or at any 

 rate somewhere along its course, fish could easily be hatched in sheltered 

 places. To be on the safe side, however, a place should be selected at 

 some distance from the springs, so that the water may contain sufficient 

 air; although it is possible that these streams contain enough air, as 

 many of them are probably nothing else but water from the Lax^, which, 

 through the numberless fissures and clefts in the lava, flows in and out 

 of the river. The water must be considered entirely pure. In passing 



