324 THE CAUSES OF THE XI 
skeleton—that of a kind of lemur—you see he 
has just the same bones; and if I were to make a 
transverse section of it, it would be just the same 
again. In your mind’s eye turn him round, so as 
to put his backbone in a position inclined obliquely 
upwards and forwards, just as in the next three 
diagrams, which represent the skeletons of an 
orang, a chimpanzee, and a gorilla, and you fin 
you have no trouble in identifymg the bone 
throughout ; and lastly turn to the end of th 
series, the diagram representing a man’s skeleton 
and still you find no great structural. feature 
essentially altered. There are the same bones in 
the same relations. From the horse we pass o 
and on, with gradual steps until we arrive at a 
at the highest known forms. On the other hand, 
take the other line of diagrams, and pass from the 
horse downwards in the scale to this fish; and 
still, though the modifications are vastly greater, 
the essential framework of the organisations 
remains unchanged, Here, for instance, is a 
porpoise: here is its strong backbone, with the 
cavity running through it, which contains the 
spinal cord; here are the ribs, here the shoulder- 
blade; here is the little short upper-arm bone 
here are the two forearm bones, the wrist-bone 
and the finger-bones. ! 
Strange, is it not, that the porpoise should hav 
in this queer-looking affair—its flapper (as it i 
called), the same fundamental elements as thi 
