260 SALMONIDtE OF BRITAIN. 



As bearing on this, Mr. Buist filled a box with unfertilized salmon ova, and 

 treated them as if they were fertile : and he observed that they never turned 

 white or opaque, like ova which had been impregnated, and subsequently died. 

 (Brown, Stormontfields Experiments, pp. 39-40, see also p. 32 ante.) 



Hybrid between Lochleven trout and Salmon smolt. 



Day, Froc. Zool. Soc. 1885, p. 242. 



December 9th, 1884. — About 400 eggs, averaging 0*22 inch in diameter, of a 

 Howietoun raised grilse, were milted from a Lochleven ti^out, but only half the 

 eggs were impregnated. About 150 hatched on February 25th, 1885, or in 78 

 days, and were turned into pond no. 4 on June 30th, very few having died. On 

 February 27th, 1886, some measured 3|- inches in length. 



Hybrid between Salmon par and American char. 



Day, Proceedings Zoological Society, 1884, pp. 40, 378. 



Nov. 29th, 1883. — Three thousand six hundred and ninty-five eggs of an 

 American char, Salmo fontinalis, were milted from a salmon par 32 months old : 

 some hatched Feb. 20th, 1884, or in 83 days. The deaths among the eggs in December 

 were 144, January 1527, February 401, or a total of 3372. On March 7th, 1884, 

 only seven were alive, and these subsequently succumbed. The amount of 

 fertilization received in this instance by char eggs from salmon par milt was 

 evidently less than that afforded to the larger eggs of the Lochleven trout. 



In the foregoing accounts of experiments on hybridism carried out at 

 Howietoun, instances have been given of cases between the salmon Salmo salar 

 in all its stages with the Lochleven trout,* and also with the American char. It 

 now becomes necessary to follow out the crossings of the trout with the char. 



Zebra Hybrids, or between American char and Lochleven trout, 



Plate XI, fig. 2. 



Day, Proceedings Zoological Society, 1884, pp. 30, 378, 585, plate Ivi. 



November 15th, 1882. — About 3000 eggs of the Lochleven trout were fertilized 

 at Howietoun with milt from an American char, Salmo fontinalis, they hatched on 

 February 8th, or in 85 days. The mortality among the incubating eggs was 

 as follows : — November 68, December 142, January 89, and February 41, or a 

 total of 340 eggs, or a proportion of about 1 death to every 6 ova. The young 

 were much malformed, monstrosities being numerous, some had blindness in one 

 or both eyes, others had bull-dog deformities of the snout. Some were very 

 light coloured, but not quite albinos, as the markings though j^ale were visible. 

 In May, 1883, I received from Howietoun one of the specimens, it was 0"8 of an 

 inch in length, the anterior portion of its head was deformed owing to want of 

 development of the premaxillaries and contigiTOUs bones, while its colours were 

 white without any markings. 



Jiily 20th, 1883. — I took fovir more specimens from the hatching box, and they 

 varied in size from 1"6 to 1*7 in. in length, while the number of par bands varied 

 from 8 to 11. The remaining fish were transferred to a large wooden tank raised 

 off the ground and supplied with water from a stream, but was rather exposed 

 to the east. 



* November the 27th, 1884.— 1296 eggs taken from a Lochleven trout were milted from a 

 male sea trout, Salmo tnitta, and on March 20th, 1875, in the afternoon, or in 113 days, about 

 900 eggs hatched, and on the 21st only 10 remained to hatch, See also experiments of Shaw, 

 Young, and Rasch (p. 48). 



