146 GIANT EXTINCT FORMS chap. 



gonia are represented to-day by a small Marsupial which has 

 been rediscovered within the last two or three years. This little 

 animal, formerly called Hijrucodon (a pre-occupied name), is now 

 termed Caenolestes, and is a native of Colombia and Ecuador. 

 There are two species, and of these G. olscurus is called by 

 the inhabitants " Eaton runcho," which means opossum-rat. It 

 lives apparently upon bird's eggs and small birds, though it 

 belongs to the Diprotodont division of the Marsupials. Caenolestes, 

 however, although diprotodont, has not the syndactylous character 

 of the digits of the feet already referred to in the Kangaroos and 

 their allies. The pouch is small and rudimentary. The denti- 

 tion is If Cf Pm |Mf = 46, and the teeth are said by Mr. 

 Thomas to be much like those of the Australian Dromicia} 



In the skull a peculiarity whiclr does not bear upon its 

 affinities to other Marsupials, but is still interesting, is mentioned 

 by Mr. Thomas. The nasals are not sufficiently prolonged to 

 meet the upper edge of the maxillae, and so a vacuity is left, as 

 in the skulls of many Kuminants {e.g. the Sable Antelope). The 

 palate is very imperfect ; the foramina, which render it so, reach 

 as far forward as the last premolar. The lower jaw has quite 

 the appearance of that of a Macropus or Phalavjjer, with long 

 and forwardly projecting incisors. 



Extinct Diprotodonts. — The great Biprotoclon is a creatm-e 

 with a skull a yard long, which must have been of the size of a 

 large Khinoceros. Thougli closely allied to Macroinis, it seems 

 that this great beast did not hop after the fashion of a Kangaroo, 

 its limbs being of a more equal size than in the Kangaroo. 

 Eecently some further remains of Dip^'otodon.hare been discovered 

 in a lake known as Lake Mulligan, where they had apparently 

 been bogged. Professor Stirling has contributed an account of 

 these remains, which fills up a considerable gap in our knowledge. 

 He has been able to state the structure of the fore- and hind-limbs. 

 Both limbs are pentadactyle, the fingers of the fore-limb being 

 approximately equal in length and general development. In the 

 hind-limb the hallux is small, and consists of the metatarsal only. 

 This bone is fixed in the position of " extreme abduction," and is 

 suggestive of an arboreal limb. Digits two and three may have 



1 Thomas, "On Caenolestes, a still existing survivor of the Epanorthidae of 

 Ameghino, and the representative of a new family of recent Marsupials " P Z S 

 1895, 13. 870. 



