The thylacine (Thylacinus cynocephalus) is approximately the size of an adult German Shepherd dog.  If Lieutenant Governor Paterson's measurements were accurate, the first specimen obtained must have been unusually large, as it had a head-body length of 1390 mm (approx. 55 in.).  Harris's type specimen was also large, having a head-body length of 1180 mm (46½ in.).  The 13 skeletons studied by Moeller (1968) had an average size of: head-body - 806 mm (32 in.), tail - 492 mm (19 in.).  The tail varies from 40-60% of the head-body length.

    The thylacine examined by Paterson weighed about 20 kg (44 lb.).  Moeller (1968) was able to find only two other records of weight - 15 and 27 kg (33 and 59½ lb.), but from a series of skeletons, he was able to extrapolate an average weight of 25 kg (55 lb.), with a range of 15-35 kg (33-77 lb.).

    Moeller (1968) took biometric measurements from a series of skeletons of various predatory mammal species, comparing the length of the limbs to that of the trunk (i.e. the spinal column minus the tail).  The thylacine's legs proved to be proportionately much shorter than those of a wolf, and are actually more consistent in form with those of dasyurid marsupials.
 

. A thylacine sitting in a rather dog-like stance.  However, the legs of the thylacine are not as proportionately long as those of dogs and other canids, and it likely stalks its prey in a rather cat-like manner instead of actively chasing it.  Old reports however, speak of the thylacine slowly but relentlessly "jogging" after its prey over long distances, gradually wearing the prey animal down to the point that it could be easily captured with a sudden rush.  This image is from a 1933 film taken at the Hobart Zoo (Domain site).

The limb length ratio therefore infers that the thylacine relies more on stalking rather than lengthy chasing of prey, and consequently would be more suited to living in forest habitats rather than open fields.  Of all the placental carnivores studied by Moeller, the most similar in limb proportions to the thylacine is the Clouded leopard (Neofelis nebulosa), a native of the Asian rainforests.  Moeller also demonstrated that the greatest lengthening of a canid's limbs are to be found at the wrist and ankle, in order to preserve the muscles' mechanical efficiency.

The feet of the thylacine are digitigrade, and differ significantly from those of dasyurids (Pocock 1926).  Striations are absent.  The digits of the manus (front foot) are rather short with blunt claws.  The pollex is quite short and its pad not particularly distinct.  Unlike those of a dog, the thylacine's toes have no webbing between them.  In canids, this webbing serves to hold the digits together when running.

. This is the right hand (manus) of a very well preserved thylacine skin (sex unknown) acquired in 1908 by the Oxford University Museum, UK.  Although the thylacine's feet are often compared to those of a canid, as can easily be seen, there are some features which are actually very un-doglike.  In particular, note the presence of a small yet reasonably developed thumb (pollex), as well as the broad design of the plantar pad.  In canids, the plantar pad is much more triangular.  Also, the thylacine's toes are comparatively more elongate, and lack webbing between them.  View detail.  Image courtesy of Dr. Stephen Sleightholme (International Thylacine Specimen Database Project).