222 TEAK-BOOK OF FACTS. 



" In the meantime there is ample scope for all in trout and grayling, two of the 

 best of British fishes, and possessing also this valuable quality, that the former 

 is in season from March to August, and the latter from August to March, thus 

 furnishing the table all the year round. To these, I think, the breeder should at 

 present confine his attention. They require no feeding, and will grow in three 

 years to between 15 and 16 inches in length, and 20 to 22 ounces in weight. This 

 seems to be the most profitable age, as after that trout lives less upon flies and 

 more upon fish, their own families not excepted, while grayling after this grow 

 very slowly. The so-called Thames trout weigh much heavier for their length ; 

 one of 13i inches weighed 17 ounces, while a brook trout of the same length only 

 weighs 13 ounces, and this difference increases as they grow older. These fish, 

 however, seem to be merely emigrant brook trout under exceptional circum- 

 stances, and do not affect the general question. Occupiers of land through 

 ■which clear streams run may breed large quantities of troul and grayling by 

 merely separating rills, natural or artificial, from the main s;ieam by fine 

 gratings, digging a few holes in these watercourses for protection to the fish, 

 and, after clearing out any x - esident fish, depositing vivified ova in the shallows. 

 Nature will do the rest." 



In a second letter S. E. says : — 



"The arts of vivifying and hatching the ova require more space than the reason- 

 able limits of this letter, for, to be practically useful, the description must be 

 minute; but I am quite willing to give it. In the meantime, t lie inquirer may 

 consult Mailer's Physiology ; ^Boccius on Fish ; Dr. Hansom on Ovas, in Proceed- 

 ings of tli> Royal Society, vol. 7 ; Carpenter's Physiology ; and the pages of the 

 Field. The difficulties in procuring vivified ova are ottcn misunderstood. The 

 poacher can furnish dead spawn, as the salmon-roe fisher well knows; but arti- 

 ficial breeding requires all its processes to be deliberate and aboveboard. There 

 is no indisposition in owners of streams to grant permission, but, if an open 

 river, the water must be carefully watched for weeks beforehand, for the spawn- 

 ing-time may begin and end in a few days, and often, just when the watchers 

 announce the fish to be ready, down comes a flood from the hills, and all is over 

 for that year. In the operations for introducing the grayling into Scotland, in 

 which I took an active part, this occurred in two out of five attempts, although we 

 had every advantage, unlimited fish, eight miles of water, and intelligent keepers. 

 The system of separate fenced-off rills gels rid of all this doubt ami difficulty, and 

 makes success certain. The old fish should be procured some months before the 

 spawning time, and placed in what we may call rill No. 1. 'When ready they can 

 be quietly removi d, and as spawned deposited in rill No. 2. The process of arti- 

 ficial spawning, properly conducted, does not in the leas! injure the parent tish. 

 The ova are mm ready for placing in the gravel of rill No. :>, aof in boxes but on 

 illows, and all else is at the command of the breeder. Vivified ova are 

 , as they are beautiful sj hares, orange- 



Coloured below (when placed in water) and semi transparent above, while 



the failures exhibits an opaque white spot. I would advise none but British fish 



or ova to be oaed al present." 



Although we do not question the utility of Fish-breeding, we must 

 not leave out of the question the facts that of the food generally in 

 use, fish <:o at din* the least nutriment, except vegetables. I; is di 

 from being often eaten out of season, and after being too long or 

 sly kept. Many of the varieties of fish are insipid and taste- 

 less ("i i water " they have been called), and to render them 

 palatable, require! more "time and acquaintance with i "'Lory, than 

 the middle or humbler classes can b rtow upon thorn. 



KBW OKAHBUKHT. 



Mr. Andrew Mn:n.\Y lias read to the Royal I'i iety, a 



notice of a N laon. This is a curiously-formed 



species of chameleon, brought from the interior of the Old Calabar 



