338 PRACTICAL AND SCIENTIFIC ZOOLOGY. 
SHRIKES. Distinguishing Characters. TYPES OF BirDs. 
1 The most rapacious of a ‘ 
Typical. b ranins the perching birds; conse- + Raptorial. 
YPIC. quently the 5 
Glossy plumage, great tails, J 
crested heads ;  conse- > Rasorial. 
quently the 
Small short feet, great heads, 
broad flat bills, dive in the + Natatorial. 
water *; consequently the 
ie Live entirely upon soft sub- ; oe 
Ceblepyrus. stances; consequently Be Grailatorial. 
Inferior only to the shrikes, 
Thamnaphitus.S in not having raptoria Insessora 
claws; consequently the 
i Edoli 
Sub-typical. CHa: 
Tyrannus. 
3. 
Aberrant. 
Here, then, it is seen, that in this supposed circle the 
Rasorial type of form is followed by the Natatorial, and 
not, as in all other birds, by the Grallatorial ; while 
the genus T’hamnophilus, whose structure, being only in-~ 
ferior to that of Lanius, shows it to be one of the typical 
groups, is placed in the aberrant division. The series 
of variation, in short, in the circle we are now testing, 
turns out to be different from that in all other groups 
of birds, and it therefore cannot be the true one. 
(416.) Our imaginary circle, therefore, not being 
able to stand the test supplied by the theory of definite 
variation, we have to retrace our steps, and ascertain 
whether an equally good circle cannot be formed 
by placing these divisions in a different series. This 
we find can be done,—the new circle is just as 
complete as the old, —and we then compare it with the 
types of variation (as above specified), as follows : — 
_ most rapacious of all the 
Typical P ranius, perching birds ; thereore Raptorial, 
; the 
Inferior only to the last, bill 
9 
aE & Thananaphitus.§ conic-shaped, claws not rasessoria. 
pap eoercae § raptorial ; therefore the 
-— 
Glossy plumage, great tails, 
Edolius, ; crested heads, gregarious ¢ sora 
habits; therefore the 
Be . Live entirely upon soft sub- : 
Aberrant. Ceblepyrus. ) stances; therefore the Grallatortal. 
Small short feet, great heads, 2 
Tyrannus. broad flattened bills, dive ¢ Natatoriai. 
in the water ; therefore the 
* See Wilson’s American Ornithology ; also Northern Zoology, vol. ii. 
‘p. 136. 
