x ORTHOPODA ORNITHOPODA 429 



apparently adult, had become embedded. Five of them are now 

 mounted in one of the public galleries of the Brussels Museum, 

 of which these perfect monsters form one of the chief attractions. 

 Having proved to be such a valuable find, they were claimed by 

 the Government, on the ground that Iguanodons were not in- 

 cluded in the license of the Coal Mining Company. The fact 

 that not only /. bernissartensis, but also a few specimens of 

 /. mantelli, already known from England, where the large form 

 likewise occurs, were found in the same place, makes the specific 

 differences somewhat doubtful ; they are perhaps sexual. 



Olaosaurus of the uppermost Cretaceous strata of Wyoming, is 

 one of the latest of Dinosaurs. It is nearly allied to Iguanodon, 

 but has only three functional fingers, the fifth being absent, whilst 

 the pollex is very short. 



Hadrosaurus s. Diclonius of the same level as the preceding 

 genus in North America, apparently also in the Middle and 

 Upper Chalk of England and Belgium, has a most peculiar 

 spoon-shaped bill, the premaxilla and the predental bone being 

 spatulate and quite toothless. The teeth in the upper and lower 

 jaws are numerous and small, and whilst one set of teeth is 

 being ground down, the several successional series are already 

 functional. If. mirabilis has in all about 2000 teeth ; the total 

 length of the skeleton is 38 feet, of which nearly 4 feet are 

 taken up by the skull ; in other respects this genus is allied to 

 Iguanodon. 



Ornithomimus, of the Upper Cretaceous of Colorado, is known 

 only from its fore- and hind-limbs. The fore-limbs are short, 

 with three fingers. The hind-limbs are very long and strikingly 

 bird-like. The metatarsals, of which only the second, third, and 

 fourth are developed, are much elongated ; the proximal half of 

 the third is pushed back between the second and fourth, and 

 imperfectly fused with them, exactly as in young birds. The 

 astragalus has a long ascending process, and is fused with the 

 tibia. The fibula is very slender, distally much reduced ; the 

 calcaneum is represented by a tiny nodule ; the terminal 

 phalanges end in pointed claws. 0. grandis must have reached 

 a considerable size, to judge from its middle metatarsal, which 

 is 60 cm. or 2 feet long. Until more is known of these 

 extraordinary creatures, nothing definite can be said about their 

 affinities. They may perhaps belong to the Theropoda. 



