Limits of Hybridisation 
cynthia and B. arrindia are fertile for eight 
generations when bred znder se. 
LimITs To THE PossIBILITIES OF HyBRIDISATION 
Hybrids can apparently only be produced 
between species of the same natural family. 
The stories of cat-rabbits, deer-ponies, fowl- 
ducks, and similar distant crosses invariably 
break down on close examination. A belief in 
such remote crosses characterized the ancient 
“bestiaries,” and still lingers, as witness the 
falsely-reputed crosses alluded to above. 
This belief has no doubt arisen from the fact 
that the domestic breeds of dogs, fowls, etc., 
are popularly confounded with truly distinct 
species. Mongrels are well known to be readily 
produced, and hence the notion arises that 
hybrids between the most widely - separated 
species are possible. 
In practice, the most remote cross of which 
authenticated specimens exist is that between 
the red grouse and the domestic fowl (bantam 
cock). It is true that the grouse are commonly 
ranked by ornithologists as a family distinct 
(Tetraonidae) from that of the pheasants and 
partridges (Pkhaszanidae), to which the fowl 
belongs ; but the relationship is admittedly very 
close, and we doubt if general zoologists would 
countenance the maintenance of the families as 
distinct. Ornithologists are notoriously apt to 
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