1885.] MR. O. THOMAS ON THE RACES OF ECHIDNA. 339 



N. H. Mainm, i. p. 47 (1846); Gould, Mamm. Austr. i. pi. iii. 

 a849). 



E. breviaculeata, Tiedem. Zoologie, i. p. 592. 



Hab. Tasmania. 



Size large. Spines short and stout, more or less hidden by the 

 long fur, especially in the centre of the back. Crown of head, belly, 

 and legs covered witn thick woolly fur, unmixed with bristles. Third 

 hind claw very nearly as stout and long as the second. 



Skull large and broad (breadth 45-50 mm., index 41-45), large 

 rounded brain-case (capacity 27 to 37 c.cm.), and a comparatively 

 short, stout snout (rostral index generally from 90 to 100). Condy- 

 loid vacuities generally present. 



It may be useful in this connection to give the synonymy of the 

 three-toed Echidna, an animal which, although not yet ten years 

 known, has become possessed of the following formidable array of 

 names : — 



Proechidna brxjijnii. 



Tachyglossus hruijnii, Peters & Doria, Ann. Mus. Genov. ix. 

 p. 183 (18/0), xvi. p. 687 (1881). 



Acanthoc/loasus bruijnii, Gervais, C. R. p. 990 (1877); Journ. 

 Zool. vi. p. 375 ; Osteogr. Monotr. p. 41 (1877). 



Proechidna bruijnii, Gervais, Osteogr., Monotr. p. 43 (1877 ; 

 Murie, J. Linn. Soc. xvi. p. 417 (1878); Flower & Garson, Cat. 

 Coll. Surg. ii. p. 753 (1884). 



Bruijnia tridactyla, A. Dubois, Bull. Soc. Zool. vi. p. 266, pis. ix. 

 and X. (1882). 



P7-oechidna villosissi/na, A. Dahois, Bull. Mus. Belg. iii. p. 110, 

 pi. iv. (1884), >c. 



For the sake of comparison, the measurements and indices of a 

 skull of this species have been placed at the bottom of the table on 

 p. 335. 



EXPLANATION OF PLATES. 

 Plate XXIIL 

 Upper view of skulls of Echidna to show geographical variation in size. 

 Fig. A. Skull of Echidna aculeata lawesi, J ; ^' of list. 



B. Skull of Echidna aculeata typica, $ ; i' of list. 



C. Skull of Echidna aculeata setosa, 5 ; «' of list. 



D. „ „ „ 6" of list. 



Plate XXIV. 

 Figs. A and B. Skulls of Echidna aculeata setosa, (S and 5 ! i'' and s' of list, 

 showing sexual difference in form. 



C. Left hind foot of Echidna aculeaia setosa. 



D. Left hind foot of Echidna aculeata lawesi. 



E. Back part of base of skull of Echidna aculeata setosa, showing open 



condyloid vacuities. 



F. Back part of base of skull of Echidna aculeaia typica, showing 



vacuities closed. 



