1885.] MR. R. COLLETT ON ECHIDNA ACANTUION. 159 



other bones of the liinbs can scarcely be shown to exist, but all are 

 perceptibly stronger in E. aculeata. 



As mentioned above, E. acanthion is furthermore distinguishable 

 from E. aculeata (and setosa) by the claws of the hind foot, the 

 third claw reaching hardly the half of the length of the second, 

 whilst in the other species these claws are of nearly the same length. 

 A corresponding difference in the strength of the respective phalanges 

 may be observed. 



Finally, with regard to the skull it has been already stated that in 

 most respects it agrees almost perfectly with that of E. aculeata. 

 Certainly the length is a little greater in the latter species (1 1 6 millim.) 

 than in E. acanthion (111 millim.); this, however, may perhaps 

 not always be the case. 



The shape of the skull, as seen from behind, appears to be to a 

 certain degree varying in both species ; but E. acanthion seems 

 constantly to have a narrower cerebral area than E. aculeata. As 

 mentioned above. Dr. Murie has described in the Journ. of Linn. 

 Soc. vol. xiv. (p. 413) a skull of the species, found by Capt. Arinit 

 at Cardwell, thus not far from the York peninsula. In his comparison 

 of the skull with five skulls of Echidnce from S. Australia and 

 Tasmania, he states that it is " barely appreciably narrower across 

 the cerebral area, but decidedly lower in the same region." This 

 feature is characteristic in all the examined skulls of E. acanthiun, 

 and is still more perceptible in the younger specimens than in the 

 full-grown. 



Thus the greatest breadth of the skull is below the foramen retro- 

 temporale, whilst the part above gradually decreases upwards ; in 

 the full-grown specimens (No. 3 and No. 9) tiiis decrease is less 

 marked, but the skull is never broader above the said foramen than 

 below, as in E. aculeata. In the latter species the os temporale 

 widens upwards (in the two skeletons preserved in the University 

 Museum of Christiania), and the greatest breadth of the skull is 

 therefore immediately above the foramen retro-temporale, not below it. 

 Finally, the snout is straight in E. aculeata (in the specimens before 

 me), but in all specimens of E. acanthion more or less bent upwards. 



Comparison ivith E. lawesi. — In March 1877 Mr. E. P. Ramsay, 

 in Proc. Linn. Soc. New South Wales (vol. ii. p. 30), described 

 an Echidna under the name of Tuchyglossus lawesi from a specimen 

 just received from Port iloresby in Mew Guinea. 



The type specimen was a skin of a male, which Ramsay considered 

 to be fidl-grown ; its length from the snout to the tip of tail was 

 13-4 inches, or about 330 millim. 



In Sept. 1878 Mr. Ramsay gave a short communication in the 

 same Journal (vol. iii. p. 244) on three more specimens, also from 

 the S.E. coast of N. Guinea. The new specimens consisted also in 

 the dried skins only, and the measurements given in tlie same place 

 may therefore also be considered as but approximative. The largest 

 specimen had a length of 16 inches from snout to root of tail, and 

 when the length of the tail is added, the total length has been about 



