1. THYLACINTTS. 255 



1. THYLACINUS. 



Type. 



Peracyon*, Gray, Ann. Philoa. (2^ x. p. 340 (1825) Th. cynoceiphalus. 

 Thylacinus, Temm. Mon. Mamm. i. p. 60 (1327) . . Th. cynocephalus. 

 Lycaon, Wagl. Syst. Amph. Sdug. p. 24 (1830) 



(nee Brookes) Th. cynocephalus. 



Peralopex, Gloger, Eandb. Naturg. i. p. 82 (1842) Th. cynocephalus. 



Size large; general build dog-like. Muzzle long and slender. 

 Ears of medium size. Tail well developed, short-haired, very thick 

 at its root. Limbs very much as in Oanis, but rather shorter in 

 proportion to the size of the animal, markedly digitigrade. Toes 

 subequal, with short, thick, conical claws ; hallux entirely wanting. 

 Pouch opening backwards f. Mammae 4. 



Shdl broad and strong posteriorly, with a long narrow muzzle. 

 Frontal region with large air-sinuses above and external to the 

 olfactory chamber. Infraorbital foramen large, oval, generally 

 divided into two imequal parts by a small bar of bone. One large 

 posterior palatal vacuity. Bullae small, transparent, scarcely in- 

 flated. Coronoid process of lower jaw much slanted backwards. 

 Axis vertebra very long. Humerus with an entepicondyloid fora- 

 men. Marsupial bones minute, unossifled, represented by two small 

 pieces of fibro-cartilage. 



Bentition-.-I. Hi^^ C. i, P. if^t M. I^|4^^x2=46. 



Teeth sharp and cutting. I.' not differentiated from the other 

 incisors. Premolars narrow, much longer than broad, separated 

 from one another by marked diastemata ; p.^ present, twice as large 

 as p.' Molars light and delicate, the main central cusp without 

 any smaller subsidiary cusp on its outer slope ; m.'' with a marked 

 central posterior talon. Lower teeth narrow and slender, not 

 crowded ; molars simple, cutting, each with a large central, medium 

 anterior, and small posterior cusp, but entirely without accessory 

 internal cusps (see PI. XXIV. fig. 1). Posterior heel of m.^ and 

 m.^ broad, its outer side raised into a small cusp, its inner side flat. 

 Heel of m.* small and simple, but distinct. 



Milk-tooth minute, rudimentary, shed during infancy. 



JRange. Tasmania onlyj. (Found fossil in New South Wales.) 



1. Thylacinus cynocephalus. 



Didelphys cynocephala, Harris, Tr. Linn. Soe. m. p. 174, pi. xix. 



fig. 1 (animal) (1808). V 



Dasyurus cynocephalus, Geoff. Ann. Mus. xv. p. 304 (1810) ; G. Cwv. 



JR. A. i. p. 175 (1817) ; Desm. N. Diet. (TIT. iV. (2) ix. p. 136 



* This name haa no claim to adoption, as ite original mention is imaccom- 

 panied not only by a diagnosis, but also by any indication of what species it is 

 intended to contain, although its author afterwards assigned it to the Tbylacine. 



t Fide Owen. 



I The occurrence in Queensland of an animal allied to the Thylacine has 

 been several times reported, but as yet these reports have not been confirmed 

 by the capture of specimens (see Scott, P. Z. S. 1872, p. 355). 



