THE WONDERS OF GEOLOGY. Lect . iv . 



been obtained from various localities of the Wealden The 

 first fragment of a thigh-bone that came under my notice 

 was a portion of the middle part of the shaft, which is of a 

 quadrangular form ; and this was so large, shapeless, and 

 unintelligible, that many years elapsed before I obtained 

 any clue as to its real nature.* The toe-bones presented so 

 little correspondence with those of reptiles, and such a 

 similitude to the metatarsals of the large pachyderms as for 

 example those of the Hippopotamus, that it was Ion « ere 

 their true affinities could be determined, f 



To convey an idea of the enormous size which some indi- 

 viduals must have attained, I may state that one perfect 

 thigh-bone is three feet eight inches long, and thirty-five 

 inches in circumference at the condyles, and that some 

 fragments indicate a greater magnitude. A leg-bone or tibia 

 of which I have a large portion, must have been four feet 

 long ; the corresponding thigh-bone would be a foot longer • 

 the entire length of the limb must therefore have exceeded 

 nine feet ! These bones occur of very different sizes • 

 I have a femur only five inches long, and other bones, that 

 must have belonged to very young reptiles. 



The femurof thelguanodon is remarkable from the combination 

 of mammalian characters which it presents, in its well-marked head 

 andneck, trochanters, condyles, and medullary cavity. Thehead {L lgn 

 107 /,) is bennsphencal and projects inwards; and a la terallv 

 flattened process or trochanter (a) forms an external buttress or 

 boundary of the neck of the bone, from which it is separated bv a 

 deep, narrow vertical fissure. The shaft of the bone is subquadran 



flat r io a n :S tly , eleVa f te(1 rid ^.P rodu - d ^ the union of tZtZ, 

 flat, long.tudmal surfaces, indicating the attachment of powerful 



• This fragment is fi gure d in Foss. Tilg. Forest, PI. XVIII 

 em^nTV , 6r - , Wi ! h that n ° We candour for ^hich he was as 

 fohows "< I S 6 ?f U1Shed aS , f ° r i" S 4t — d -t 8eni M , ™te to me as 

 IrTl SmenS d0S du m «acarpe on du mgtatarse, sont si 



HKoZr iCr C ° UP *■" je ' eS "* ** *" ~ d '«» *'-> 



