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had assumed in fact its final form from which it hardly departed 
in the least particular in descendants as remote, and in other 
respects as diverse,as the modern Emu. The lecturer illustrated 
this point with sketches of the bones of the foot of Iguanodon 
and of a natural cast of the foot itself found near Hastings. 
Other points of structure in which the Ornithopoda, or Bird- 
footed division of the Dinosauria, seemed to fore-tell the coming 
race of Birds, were the cellular structure of their bone and the 
horny processes (beaks) with which both upper and lower jaws 
of the Iguanodons terminated. 
At this point the Pterodactyls were referred to, true flying 
reptiles who flourished in Secondary times, and which seemed in 
some cases to have acquired several bird-like characters such as (in 
some species) toothless beaks, cellular bones, and a keeled ster- 
num upon a totally independent line of evolution. They flew by 
a patagium or extension of skin or membrane stretching from the 
sides of the body (sometimes from the lower limbs even) to the 
outer edge of an enormously developed little finger, but there 
was no reason to suspect them of feathers, and although some of 
their remains are exceedingly bird-like at first sight, it seems 
probable that the birds descended through the giant terrestrial 
dinosauria, using their acquired pelvic arrangements first for 
land progression then for swimming. It was probably during 
an amphibious interval in the evolution of the bird, that the 
fingers of the fore limb became webbed and the down upon the loose 
skin (patagium) of the back of the arm developed into something 
approaching the swimming paddles of the auk and penguin. 
From such an arrangement used first under water (as diving 
birds still used their wings), then along the surface as the steamer- 
duck and many species still used them, the steps to partial and 
then to perfect flight were at least thinkable. 
These steps, however, were matters of conjecture. From 
various causes bird fossils were among the very rarest of all 
animal remains. A bird in nature usually escapes just those 
accidents, bogging, engulfing, &c., to which we owe the preserva- 
tion of mammalian and reptilian remains. It was well seen to 
be no part of the scheme of nature to preserve a complete record. 
We knew hundreds of species by their teeth alone, yet birds, 
speaking broadly had no teeth ; no one had been bold enough to 
describe as avian any detached teeth from secondary or earlier 
deposits. Birds’ bones were usually small and always more 
fragile than those of other animals, hence the particular family of 
reptiles which varied in the direction of bird-like lightness and 
