POPULAR SCIENCE REVIEW. 
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a large anterior pre-pubic process, which may be considered 
Lizard -like or Chelonian, but is not altogether unparalleled by 
the small pre-pubic process of the Apteryx. Professor Marsh 
has described more than one remarkable modification of this 
type of pelvis, which appears to show that a distinctive 
Reptilian feature is retained, even after the bones acquired the 
closest possible resemblance to Avian forms and manner of 
arrangement. The pre-pubic process, however, might be 
regarded as analogous with the pre-pubic bones of Ornitho- 
saurus and Monotremes, although in those groups it is a distinct 
ossification. 
The hind-limb offers a nearer resemblance to that part of 
the skeleton in a bird, than in any other animal, and is much 
more bird-like than the hind-limb in any existing reptile, but 
its Avian characteristics have probably been over-estimated 
(Fig. 10). The femur, or thigh-bone (Fig. 14), is long and 
strong, and readily recognized by three characters : first, the 
depth to which its head is received into the cavity in tbe 
ilium, which usually makes the whole of the upper, or proximal 
end of the bone an articular surface, and renders it impossible 
to define the head of the bone from its shaft, because there is 
no constriction between them ; secondly, there is almost always 
a slender free process, or trochanter, directed upward on 
the outer front margin of the bone, which appears to correspond, 
in part at least, to the great trochanter ; and, thirdly, on the 
inner border of the shaft of the bone, at, or above its middle 
part, is another trochanter, compressed from side to side, 
usually called the third, and regarded as peculiarly Dino- 
saurian, which is nothing but the lesser trochanter of the 
mammalian femur somewhat differently placed. This latter 
conclusion is satisfactorily demonstrated by remains of a new 
genus from the Upper Greensand of Gosau, placed in my 
hands by Professor Suess. Here a strong muscular crest, 
which may be exactly compared to the posterior ridge 
between the trochanters on the human femur, sweeps down 
in a curve from the outer and upper margin of the hinder 
side of the bone to the inner trochanter. But though the 
aspect of the femur thus becomes Mammalian, the bone is 
nevertheless modified from a Crocodilian plan. If we suppose 
the head of the Crocodilian femur to have the apex of its 
triangular outline on the middle of the inner margin immensely 
enlarged at the expense of the anterior part, it becomes Dino- 
saurian. And on the middle of the inner side of the shaft 
of the bone the Crocodile has a trochanteroid thickening, 
which corresponds with the inner or 4 little ’ trochanter of 
Dinosaurs; and just as in the Gosau specimens, an ‘inter- 
trochanteric ’ muscular ridge extends from it upward and 
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