HYBRIDS BETWEEN THE TURBOT AND THE BRILL. 297 
the context. I propose, therefore, to discuss the question very 
briefly in this note. 
In the appended woodcut, Fig. 2, a is a group of scales and cap- 
sules from the lateral line of a hybrid (blind side), and the resem- 
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Fi¢. 2,—a. Group of scales from region of lateral line of hybrid (blind side). 4. Group 
of scales from base of interhemal ridge of hybrid (blind side). ¢. Tubercle and surround- 
ing papille of turbot (ocular side) ; pigment omitted from papille. 
blance to true scale capsules of the lateral line of the normal turbot 
is sufficiently noticeable. The surrounding scale capsules, however, 
are far more regular than the papille of the turbot, besides enclos- 
ing a very conspicuous ovoidal scale. In a group of scales (b) from 
the base of the interhemal ridge of a hybrid (blind side) we find 
that the sulci, in this case obviously in connection with true scale 
capsules, present an appearance closely similar to those met with 
between the papille of the same region in the turbot. c shows 
a single tubercle of a nearly adult turbot (ocular side) surrounded 
by a group of papille, the apex of the tubercle projecting through 
the skin in precisely the same manner as I have described in the 
case of some of the scales of the ocular side in the hybrids. The 
smallest turbot (42 inches) in which I have found the tubercles 
visible to the naked eye has these structures in the form of blunt 
cones, the bases of which are elongated anteriorly, but entirely 
destitute of radical processes. Radial insertion sulci are also 
absent, but such is also the case in some scales of the hybrid. In 
fact, save that it is much thicker in proportion, the young tubercle 
of the turbot is not distinguishable in structure from the scale of 
the hybrid. The tubercles of the turbot, as is well known, have 
no regularity either of disposition or of number, and I think 
that there can be little doubt but that the mtervening papille are 
merely barren scale-sacs, which become to some extent broken 
up and anastomosed with the growth of the fish. If this is the 
case the intermediate nature of the scales of the hybrid becomes 
apparent. 
More sparingly distributed than those of the brill, though more 
numerous than in even the most thickly tubercled Norwegian 
