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dorsal fin; the largest fish was four inches long. July 5th, 
1886, doing well. November, 1886, their colours were very 
similar to those of the “ zebra ”’ breed, only. being a little more 
plum-coloured along the sides, the dorsal fin less marked, and 
the head darker ; consequently those hybrids which contain 
one-fourth Lochleven trout blood and three-quarters of that of 
British and American chars commingled, have adopted the 
colouring previously observed in hybrids between the American 
char and Lochleven trout, while the tints of the British char, 
Salmo alpinus, were almost absent. This, it will be observed, 
was a second cross, the first being between the two species of 
char, and the resulting fertile hybrid being subsequently crossed 
with a pure Lochleven trout, a form which was absent from 
either of the parents. The original American char eggs were 
received from America, and the British char from Loch Rannoch. 
Eggs obtained from one of these hybrids, were milted from 
another of the same lot, but none of them hatched. 
A two-year-old hybrid, half American and half British char, 
was crossed on November 15th, 1887, by a male Lochleven. 
About 3,000 ova were procured, and on February 38rd, 1888, 
about 300 hatched. Among them were many deformities. 
In crossing two forms of char, the mode of dentition on the 
vomer, or teeth, being restricted to the hind edge of the 
head of that bone, naturally remains unaltered in the hybrid 
progeny ; but when hybridization is continued by crossing char 
with trout we at once see that a very decided alteration in the 
situation of these teeth takes place. Trout, as is well-known, 
have not only teeth along the hind edge of the head of the 
vomer, but likewise along the shaft or body of that bone. But 
in the intercrossed forms we observe a short single row of teeth 
along the anterior portion of the shaft of that bone, and which 
reaches its head, which is shortened posteriorly. Irrespective 
of this distinct structural difference of such hybrids from other 
known European forms among salmonide, the external colours 
are likewise forming a distinct character for themselves. In 
all they are seen to be covered with vermiform or reticulated 
