38 DR. J. MURIE ON IRREGULARITY [Jan. 13, 
isnot a Salmon. It must be borne in mind, moreover, that in my 
previous communication I stated that the number of scales counted in 
the specimen was not rigidly accurate, those given as transversely 
inclined to the long axis of the body being decidedly under rather 
than above the precise amount. I say so advisedly ; for on reexa- 
mining specimen No. 1, and taking a linear row of scales slightly in 
advance of the point previously chosen, and therefore more in ac- 
cordance with Giinther’s plane of obliquity, I find that twenty-one 
or twenty-two (?) are definable. But howsoever this may be, the 
penultimate column to the right of the table here given (p. 37) 
conclusively demonstrates that, even in limited numbers of scales, 
the dubious specimens in question agree less with the undernoted 
species of Salmo than with S. salar. 
Lastly, this remark applies with still greater force to the scales 
counted linearly from the lateral line to the ventral fin, with the 
proviso that those of the lake fishes of mid-Europe are unrecorded. 
II. Uncertainty of the species.—Upon this point it need only be 
said that, if not Salmo salar, it is most remarkable, and fatally telling 
to the denial of parentage, that the fish correspond to none of the 
European types, either in size, markings, or other distinguishing 
characteristics. Had therefore a mistake happened as to the recog- 
nition of the ova, this would have ultimately rectified itself in the 
development of the specific characters applicable to adult piscine 
form. 
Ill. The question of hybridity—As respects hybridity, which 
Dr. Giinther suggests may-be the case with those specimens reared 
in the Gardens, it becomes rather an important item of deliberation. 
On what grounds can it be assumed we have hybrid fish to deal 
with, granting, for the time being, no set line of demarcation proving 
their identity with a single specific form can be given? 
1. The produce of different species may have been fertilized at the 
Rhine fish-hatching establishment. 
2. Instances of hybrids among certain of the Salmonidee are stated 
to be of no uncommon occurrence. 
3. Our specimens possess resemblances to none of the well-esta- 
blished forms, but have appearances indicating intermediate origin. 
As experiments prove, the fertilization of the ova of one piscine 
form with the milt of another distinct species is beyond controversy 
exemplified in hybrids between the Salmon and the Trout. It 
is needless therefore to shirk the reasonable contingency of inter- 
mixture of breed having accidentally or intentionally supervened. 
Against such a circumstance it can be advanced that, so far as is 
known, the authorities at Huningue did not with intent form a 
cross breed and transmit the impregnated ova of such to this 
country as pure Salmo salar. Moreover, to the practised eyes of 
Buckland and Bartlett, the ova were those of Salmon; and the 
period of hatching coincided with that of that fish rather than with 
that of the Great-Lake Trout, Charr, Salmon-trout, or Common 
Trout, received in the beginning of the same year, 1863. This fact 
also tends adversely to the presumption of accidental hybridity. 
