TIVnRTD.S— STllUAN RACM. 2G5 



Scotch cliar ; the deaths among the incubatiiit^ Co^y \^'i'''<-'. i'l Dccenibci' liiH, 

 January 7S7, February lOi — or a total of 11 H> ; they hatched on Fcbru:iry IGlh. 

 ;^^arch 13th, 1881, upwards of lOO were present. On April 2tth, 1885, they were 

 shifted to pond 5, along with similar hybrids. 



Struan Hybrids crossed. 



Day, Proc. Zool. Soc. 1885, p. 243. 



November 12th, 1884. — Afomalo struan hybrid, twenty-one months old, gave 14(3 

 eggs, which were milted from a male of the same breed. Only six liatched on 

 February 3rd, 1885, or in 84 days. 



Struan Hybrids crossed. 



November 24th and 25th, 1885. — Aboxat 17,500 eggs were obtained from struan 

 hybrids, and crossed by males from the same breed, they being at that time tliirty- 

 threc months old. The mortality from the two lots was, in November 5735, 

 January 5635, and February 393; 1054 were unimpregnatcd. They commenced 

 hatching February 11th, and about 2000 young came out. Many were very weak, 

 and the mortality became considerable. July 30th, 689 fish were shifted to 20 feet 

 pond no. 3 ; and on December 27th 450 were moved to the botanical pond, which 

 is about four feet deep. About the middle of June, 1887, and the subsequent three 

 weeks when the weather was scorching and the glare great, many were observed to 

 commence to lose their colour, to become somewhat similar to albinos, with the 

 pectoral, ventral, and anal still showing the red colour. On a net being placed 

 near them they did not move unless touched, and on being taken out of the pond 

 were found to be blind : in those slightly affected in colour the pupil was fixed and 

 the colour dull, almost opaque, in those fully affected it was quite opaque. At the 

 commencement of July some wood was placed over the inlet end of the pond under 

 which the fish crowded, hut the temperature of the water did not fall until some 

 rain fell on the 5th and 7th, when the fish seemed more lively. Some boards were 

 now placed over a portion of the pond for the char to get under, but no other 

 locality was available in which to transfer them. This instance is interesting, as 

 showing how excess of light and heat, added to insufficient depth of water, causes 

 mortality among these fishes. 



Struan Hybrids crossed. 



November 5th, 1886. — Twenty thousand eggs of this form of hybrid, 45 months 

 old, were milted from males of the same race, the mortality being, in November 6895, 

 December 4397, January 1503. This cross was repeated next day with 6000 eggs, 

 and the mortality among them was, November 2526, December 1257, January 657, 

 and 675 were not impregnated. They commenced hatching January 13th, and 

 continued doing so for sevei'al days. Some of these hybrid parents were two 

 years old, others a season older. As a rule, to which there were exceptions, these 

 fish were weak. On June 14fch, 1887, 1250 were placed in box 4, and 1000 in box 

 no. 5 in the hatching-house. 



Struan Hybrids breeding. 



December 6th, 1884. — Six hundred ova were ohtained from a 22 months old struan 

 hybrid. These ova had an average diameter 0'15 inch, and were milted fi'ora 

 another struan hybrid and placed in box 104?;. February 23rd, or in 79 days, 50 

 hatched and were transferred to box no. 92, but only one lived, and it was placed 

 in pond 3. 



