112 GILPIN ON THE GASPEREAUX. 



the dry season, and go down during the August freshets. Finally, 

 October seems to be the last date for even the fry to be seen in 

 fresh water. 



We have thus received the Gaspereaux from the moment he left 

 salt water, conducted him through all his perils, and had him as it 

 were under our eye till we have returned him to deep water again, 

 three months out of the twelve. The other nine months he is hid 

 from us. They are taken in small numbers, generally with herring, 

 sometimes with the mackerel, as late as 24th November, on our 

 coast, but they are evidently only stragglers, the great body that 

 swarmed our rivers must leave our coast, to return in spring. They 

 return either to deep soundings or to the south. And now a change 

 takes place in the colour of a few individuals, that is, so far, un- 

 accountable to us. After gainmg the salt water the lean weak fish 

 rapidly recruits, becomes silvery, very fat, and a few individuals 

 have a deep blue band of one inch and a quarter extending along 

 the back. In all other respects — of fins and fin rays — they are 

 identical with the rest. Our fishermen call them blue-backs, 

 readily distinguish them, and maintain them to be a separate fish. 

 Whilst differing from them, I must accord my obligation to their 

 intelligence and exact appreciation of minute differences, in the 

 form and habits of fish. On the 15th November, 1864, Martin 

 Harrigan gave me two blue-backs ; 27th November, two more 

 specimens. 



Colour. — Very brilliant ; silvery, with deep blue backs extending one 

 inch and a quarter doAvn the side. Covered with nacre, and scales entire, 

 the longitudinal bands extending from gills to tail difficult to see, — the 

 black spot behind the opercle showing, — by turning them in various 

 lights thej become apparent ; the colour of all the fins yellowish white ; 

 the extremities dusky, in pectoral first ray dusky ; the caudal light-dusky, 

 frayed and split on its extremities ; opercles yellowish, with reflections, and 

 lips yellowish-dusky. In comparing them with a gaspereaux taken at the 

 same date, I find fins, fin-rays identical ; the blue-back is rather shorter, but 

 much rounder and thicker through the sides, the scales appearing larger. 



A gasj)ereau seen at this late date being very thin, "slinky" 



as the fishermen call it, his scales loose, and his colour yellowish 



silvery, and green dusky on the back. A very fat fish swells out 



the scales, making them larger ; as he thins they slide in upon each 



other. Whilst concluding that they are of one species, I still think 



that the salt water is the cause of the change ; but why it only 



