MONOGKAPH OF THE FALCONID.E, 
by the family Tcmtalidce , and among the Macrodactyli perhaps by 
the family Hallidce. 
Among the suborder, Brachypteri, the swallow type is not clearly 
expressed in the family Uridce , but it is very clear as the genus 
Tachypetes among the Pelicanidce. Very long quills and short 
covers and secondaries, very short tarsi and forked tail ; this is an 
able and perhaps the most energetic flyer among the whole class. 
Among the Lamellirostres , the swallow type is represented by 
the family, Anatidce, and among the Tetraonidce, by the genera 
Pterocles and Syrrhaptes . 
Having now assigned the second rank to all the suborders, fami- 
lies, and subfamilies, which represent the true Ornithes or swallow 
type, we now return and ask ourselves, What is it that constitutes 
the third class ? Heptiles, what are they ? What is, in fact, the 
distinguishing characteristic of a reptile % 
In the third class, the reptiles, the system of the bones has 
arrived at its highest possible perfection. In no other class do we 
find the vertebral column so strongly expressed as in this one ; here 
it shows the greatest number of vertebrae and ribs. — (100-300 ver- 
tebrae with ribs among the serpent.) In this class we find such a 
mass of bones (Co lossoche llis, Iguanodon) as in no other; it contains 
the longest and most enormous forms of creation. Among the rep- 
tiles, being the counter part of the birds, we see the hind-legs often 
elongated, developed at the expense of the small fore-feet, as in the 
Frog, Lacerta, Agamidce, Crocodilidce. 
In this class appear the shortest as well as the smallest and the 
most variable number of toes ; and generally also in animals belong- 
ing to it, we first observe extremities really divided into fingers, 
comparable to those of the mammalia. The muscles are not in 
proportion to the enormous mass of bones ; this with their smaller 
consumption of oxygen, and the slow circulation of their blood, 
makes them to be inert creatures, which, during a greater part of 
the year exist in a state of lethargy. In this class first appear 
two pierced nostrils, respiring the elastic air at the end of a head, 
often very much prolonged (Crocodilidce). The greater number of 
the reptiles love humidity, morasses, though there are many of them 
also living upon trees or in deserts. 
They are Nose-bone-torso or vertebra} animals. If we apply 
these characteristics to the class of birds, and look about for ana- 
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