FRESH-WATER TROUT— COLOURS OF. 201 



while occasionally, especially when within or near tidal influence,* thcso black 

 spots may assume an X -shape, or be starred. , , , , . , , c 



Or the trout may be of gorj,a'ous purple along the back and sides, and of 

 a c^olden tint along the belly, more especially during the breeding season. These 

 may be spotted similarly to the first variety, except thiit star-shaped markings are 

 rarer, and red spots more numerous. This colour is frequently seen m such trout 

 as frequent tidal localities, although it pertains more to fresh water. 



Various causes will occasion these fish to be dark-coloured, and almost 

 invariably with black spots, and often with red ones likewise. This dark colour 

 would seem to be generally owing to the colour of the water in Avhich they reside 

 as when much impregnated with peat. To the depth of water in which they live 

 as in some large and deep lakes, and when char similarly live there, as in Loch 

 Rannoch, in Perthshire, they are equally of a dark colour. Age also is probably 

 a factor inducing darkness of colour. 



In some forms the finger marks of the par are found to be persistent m the 

 adult, as is most commonly perceived in small forms, or rather in trout which 

 due to living in small streams have not attained to any size. Sometimes these 

 finger marks appear after death. 



In many places the dorsal and anal, and often the ventral have a white outer 

 edging, interior to which is a narrow black base. This is most frequent in southern 

 formsr'but not so invariable in the loch trout of Scotland, while it is generally 

 absent from Lochlevens, when reared near their original habitat. This deficiency 

 of the white border becomes lost when the fish are removed to another locality 

 where it is the prevailing type. In June, 1886, I examined a large number of 

 trout from the river Loanan, in Sutherlandshire, passing from Loch Awe to Loch 

 Assynt, the cjecal appendages varied between 46 and 50. The white anterior 

 edging to the dorsal fin was very slight, black spots were large and distinct on 

 the body and fins, a few red spots existed along the lateral-line, and a few more 

 were scattered over the body. Examples from Loch Awe were more spotted, had 

 no light edge to the dorsal fin, and were generally purplish with yellow bellies. 

 Here the Loch Awe trout were intermediate in colouring between burn trout and 

 Lochlevens. However, on April 23rd, 1886, I examined some trout at the 

 Windrush in Gloucestershire, the white edge to the front of the dorsal fin was 

 not distinct, neither was the black base, but the fin was closely spotted with 

 black. The opercles of those not quite in condition had a green tinge, but m those 

 in condition it was purple. The stomachs of all were distended with water snails, 



* We find trout assuming a silvery appearance owing to changing their abode to salt water : the 

 fishermen at St. Andrews, sometimes after floods in the rivers, capture them in the stake-nets in 

 the bav Mr. Dunn observed, May 1st, 1884, upon a fresh-water trout having been taken m 

 Mevagissey Bay. Dr. Giinther, Catalogve, vi, 1866, p. 357, remarked that " specimens of Salmo 

 fario freniiently descend to the sea and assume a bright silvery colour with numerous X;shaped 

 spots." While he deposed in the " yellow-fin case," 1872, "I do not know of one single instance 

 in which Salmo fario living in running streams assumed the silvery appearance (P- l^^)- 

 E B L , writing 'to The Field, March 27th, 1886, remarked on four trout, -S. Jarto, about J lb. 

 each' taken in the Kent, Westmoreland, below Sedgwick, immediately below the Basinghall weir. 

 " They were in unusually excellent condition, plump and clean, so much so as to attract the special 

 attention of Mr. F. Fulton, their captor. In admiring their beauty he noticed that all had sea 

 lice upon them. We all know that the ordinary brown trout lives and thrives in brackish ^yater, 

 but this is the first instance that has come to my knowledge where Salmo Jano has stayed 

 sufficiently long in the sea to have the parasites mentioned attach themselves to him. On the 

 same river, right away to the bay of Morecambe, I have caught numerous trout, some actually m 

 brackish water, but none of them bore the sea lice." ^ . e *i„„^ 



Mr W. Anderson-Smith, writing to me the same month from the west coast of Scotland, 

 observed, " My little boy brought in a lot of brook trout from the stream at Naun yesterday, and 

 aU were covered with light silvery scales. They were not far from the sea, and had no doubt 

 been thither. They seemed to be silvered by the salt water." Mr. H. G. Henderson March 12th 

 1887, observed, " I caught a trout last year in Ireland about 3.^ lb. ; when taken out of the water it 

 had a silvery appearance like a salmon, but the following morning the distinct marks of the trout 

 appeared upon it." This instance would seem to be one of a fish returning from a sojourn in 

 salt water. 



