V SPECIES OF ECHIDNA I I I 



In the skull the Echidna differs from Ornithorhynchus in 

 the greater extension backwards of the palatines, and the larger 

 size of the pterygoids. The extent and relations of these bones 

 to each other is not at all unlike that which obtains in many 

 Whales. The premaxillae show traces of the same divergence 

 followed by convergence of their ends that is seen in the 

 Platypus. There are only sixteen pairs of ribs, and either 

 three or four lumbar vertebrae. Eclcidna has no trace of teeth, 

 and there are no horny pads which take their place ; the mouth 

 is as edentulous as in the true American Anteaters. The brain 

 (Fig. 53) is marked by sulci, contrary to what we find in 

 Ornit]iorhy7ichvs. The genus has been divided into three species, 



Fig. 54. — Australian Anteater. Echidna acul&Ua. x i. 



but it is doubtful whether more than one can be allowed, which 

 ranges from Australia through the Papuan region. While there 

 is but one species of true Uchidna, a New Guinea species must 

 clearly be referred to a distinct genus Proechidna} This animal 

 is to be distinguished by the fact that there are usually l:)ut 

 three toes on each foot. But there are copious rudiments of 

 the other phalanges, upon which claws are sometimes developed. 

 The beak is curved downwards, and the back is rather arched ; 

 the whole animal has the most singular likeness to an Elephant ! 

 The ribs are increased by one pair, and there are foiu' lumbar 

 vertebrae. The one species is named P. hrvijnvi. The Hon. W. 

 Rothschild ^ distinguishes a form P. nigroacuhata, which is allowed 

 by Mr. Lydekker. 



^ Zarjlossris has apparently priority as a name ; but Proechidna is better known. 

 - Proc. Zool. S'oc. 1892, p. 545. 



