3. ONYCHOGALE. 73 



Type. 



[3. ONYCHOGALE. 



Onychogalea, Gray, drey's Austr., App. ii.p. 402 (1841) ; 

 id. List Mamm. B. M. p. 88 (1843) {nee Gray, P. Z. 8. 

 1864, pp. 509, 570) O. unguifera. 



Rhinarium hairy, the bottom of the internasal septum alone 

 naked in some species. Central hind claws long, narrow, com- 

 pressed, and very sharp. Tail long, tapering, short-haired, not 

 bushy, more or less crested towards the tip ; its extreme end pro- 

 vided with a peculiar horny epidermic excrescence, forming a spur 

 or nail at the tip. 



Skull much as in Macropus. BuUse more or less inflated. 



BentUion :-L \^„ C. »fi, P. |^|4^, M. h|t|rl X 2 = 32 

 or 34. 



Incisors small and light, decreasing evenly in size from before 

 backwards ; i.^ and i.^ very slender, slanting strongly forwards ; 

 i.' thinner and lighter than i.^, its edge considerably shorter than m.^ 

 or even p.'', its notch about its centre (see Plate IX. figs. 10 & 11). 

 Canines small or absent. P.* small, hourglass-shaped, without in- 

 ternal ledge. Molars as in Macropus. 



Range. AU Australia. Not found in Tasmania. 



The Nail-tailed Wallabies form a natural little group, distin- 

 guished both by the shape of the incisors and by the peculiar 

 horny excrescence at the. tip of the tail. This latter character is 

 altogether unique among Marsupials, and is only found among 

 other Mammals in the Lion, which sometimes has a somewhat 

 similar horny spur at the end of its tail. In the case "Df the Wal- 

 labies it is difficult to conceive what can be the use of the spur ; 

 and observations on the living animal are much needed with regard 

 to this interesting point. 



Synopsis of the Species. 



I. EXTEENAL ChARACTEES. 



A. General colour fawn. Tail very long, its ter- 



minal nail large, flattened 1. O. wiguifera, p. 74. 



B. General colour grey. Tail medium, its ter- 



minal nail small, rounded. 



a. White shoulder-stripes running forwards 



along back of neck ; centre of neck black 



or grey 2. O.frenata, p. 75. 



b. White shoulder-stripes ending above sca- 



pulce ; neck dark rufous 3. O. limata, p. 77. 



II. Craniax Chaeacieks. 



A. Forehead inflated. Canines present. P.^ more 



than 4 millim. long 1. O. unguifera, p, 74. 



B. Forehead flat. Canines minute or absent. 



P.* less than 4 millim. 



a. Palatal foramen equal to or longer tham m.^ 



Bullae but little mflated 2. 0. fi-enata, p. 75. 



b. Palatal foramen shorter than m.^ Bullae 



much inflated 3. O. lunata, p. 77. 



