184 SALMONIDiE OF BRITAIN. 



end of September, according to locality, in tlic coast streams from June 1st 

 to the end of August, and in the Wakatipu streams in September. In certain 

 rivers the trout now seem to be migratory, so it would almost look as if they 

 were commencing to be anadromous like the sea trout, for, as observed by Mr. 

 Arthur, migration appears to be the refuge of trout in Otago when planted in a 

 stream deficient in size, range of water and food. Thus the largest trout 

 disappear from the waters of Leith, except during the breeding season (see 

 p. 7 ante). As to the colours and markings of those in the rivers of Otago, 

 considerable variations are seen, a general feature being that females of any age, 

 and from any stream, arc silvery with black spots, red ones being seldom present 

 or numerous, while the males are darker with a tendency to yellow on the sides 

 and belly ; at times they are very golden and as a rule they have red spots, some- 

 times large and numerous, the shape of the black spots always being round on the 

 gill-covers, shoulders, dorsal and adipose fins, but varying on the body from 

 round to rectangular and x -shaped spots towards the tail. The theory that a 

 salt-water residence occasions black spots to become of an X -shape is not borne 

 out by facts. For example, trout of both sexes, in clear and white water with a 

 light bottom, as in the Shag river, Pomahaka, and Wakatipu lake, are silvery and 

 have black spots mostly x -shaped ; bright silveiy females with fine heads and 

 X -shaped spots may often be seen, that might easily be taken for sea trout. 

 While the Waiwera and Waipaki rivers, which have dark bottoms, produce trout 

 of the golden variety, with most of the black spots rounded in form. The food 

 in these four rivers is much the same.* 



Another experiment on the dissemination of trout may likewise be alluded to 

 in this place. When at Ootacamund on the Neilgherry Hills in the Madras 

 Presidency in 1863, I observed a deficiency of fish in the waters of the upper 

 plateau. These mountain ranges embrace a geographical area extending over 

 268,494 square miles ; their peaks vary from 6000 to 8000 feet above the sea, and 

 Ootacamund is 7426 feet above the sea level, with an annual mean temperature 

 of 68°68' Fahr. I proposed to the Governor of Madras attempting to introduce 

 fresh-water ti'out from England by means of their eggs, and attempted it in 

 1866, and although I failed, Mr. Mclvor, acting on knowledge acquired in my 

 failure, succeeded in 1868 in bringing out some trout fry from Loch Leven, which 

 in due time bred in their new home, where, as will be subsequently adverted to, 

 they developed red spots which are generally absent from the true Lochleven 

 trout, t 



* Mr. Arthur (Trans. Otago Institute, July 9th, 1878) also remarked that unhke the Scotch 

 trout, which according to Stoddart show a yearly increase of about one-third of a pound in weight, 

 in Otago they grow so rapidly and arc so fat, that they have reached an average yearly increment 

 of from 1 lb. to 2f lb. Already the various streams have stamped the trout with local peculiari- 

 ties: in some they are plump almost to deformity ; their proportions are not constant neither are 

 their colours, while examples have been seen up to 20 lb. in weight. In 1882, one 31 inches long 

 and weighing 19 lb. was caught at Tcmuka, its flesh was of a pale orange : in 1881 Mr. Gwatkin 

 captured one in Canterbury, that turned the scale at 21 lb. 



The foregoing facts corroborate the view that all our forms of trout are varieties of one species, 

 and the hybrids we hear so much about are not mules but mongrels, being the result of the 

 crossing of varieties of one species. Consequently sterility need not be anticipated ; but, on the 

 contrary, improvement is more likely to ensue (should there be no deficiency in food) than when 

 the stock is bred in and in. 



f Dr. Giinther, in Tlic Zoological Record of 18C7, remarked of the above experiment that " an 

 attempt to introduce trout into the waters of the Neilghcrry Hills has failed (as has been foreseen 

 by all acquainted with the nature of Salmonoid fishes)." In The Journal of the Linnean Society, 

 187('>, Zoology, vol. xii, p. 562, I recounted how trout had bred on the Neilgherry Hills, and I 

 exhibited at a meeting of the Society an example raised at Ootacamund G-5 in. in length. Only 

 the name of the paper was admitted into Tlie Zoological Bccord for 1S7G. In my Fishes of India 

 and Ceylon, Part III, August, 1877, p. 508, 1 gave a short sketch of what had been done in Madras, 

 and figured the Neilgherry specimen of trout, life size, Plate cxviii, iig. 3, but all reference to 

 it was omitted from Tlie Zoological Becord for 1877. Dr. Giinther subsequently remarked in his 

 Introduction to the Study of Fis]ies, 1880: " Thus, the river trout or sea trout were very proper 

 subjects for those eminently successful attempts to establish them in similar latitudes of the 

 southern heiBisphere, whilst the attempt of transferring them into the low hill streams of India 

 ended (as could be foreseen) in a total failure " (p. (ill). In these observations Dr. Giinther 

 appears to have overlooked the following : — Firstly, that streams at upwards of 7000 feet above 



