496 MR. R. LYDEKKER ON SCELIDOTHERIUM. __[Nov. 16, 
S. bravardi. Should, however, any of my fellow workers be able to 
identify it with either of such forms, I shall be only too happy 
to relegate this name to the rank of a synonym. 
The structure of the astragalus of S. bravardi (as Dr. Burmeister 
remarks in his description of the larger form which I provisionally 
associate) approximates very strongly to that of Megatherium, 
although wanting the articular cup for the navicular ; and it is there- 
fore probable that the hind foot of this species was more everted 
than in S. leptocephalum. ‘The shorter nasals of the present species 
also diverge less widely from the Megatherium type than do those of 
the last-named species, and this character is still more developed in 
the following form. 
ScELIDOTHERIUM CHILIENSE, Nl. Sp. 
The form to which I propose to apply the above name is repre- 
sented by a series of specimens purchased during the present year 
by the British Museum, from a gentleman residing at Lima, which 
were obtained from the Pleistocene of Tamarugal, in the district of 
Tarapaca in Chili’. The specimens comprise three more or less 
imperfect crania, the anterior portion of a mandible, and a consider- 
able number of vertebree and limb-bones. All that I have to say in 
regard to the limb-bones is, that the astragalus is intermediate in 
structure between that of S. leptocephalum and that of S. bravardi, 
and that the humerus has a well-defined entepicondylar foramen. 
The least imperfect of the three crania is represented in Plate 
XLVIII., and shows nearly the whole of the nasals. The most 
striking feature of this cranium is the extreme shortness and breadth 
of the latter bones—their length not exceeding one third of the total 
length of the cranium—while the mandibular symphysis is also 
equally short, as will be seen by the following measurements. That 
this form is totally distinct from S. leptocephalum is self-evident. It 
appears more nearly allied to S. dravardi, with which it agrees in the 
prominence of the lachrymal, the narrowness of that portion of the 
maxilla appearing on the frontal aspect, the straight facial profile, 
and the narrowness of the interdental portion of the palate; but 
differs by its greater width, by the still shorter facial portion, by the 
probable abortion (as will be shown below) of the premaxille, and 
by the shorter anterior portion and symphysis of the mandible. 
The mandible is quite unlike that of S. tarijense*, in which the 
symphysial part is bent upwards very suddenly, nearly the whole of 
it being above the level of the dental alveoli. The nasals of that 
species are also much longer than those of the present form. 
With the skull of the so-called Platyonyx brongniarti from Brazil, 
figured by Lund in the K. Danske Vid. Selsk. Skr. vol. ix. pl. 
XXvill., the present specimens agree very closely in general characters ; 
but in addition to being of superior size, the cranium is relatively 
narrower, and lacks the marked expansion behind the nasals, while 
1 See map, supra, p. 396. 
* T refer to this species a left mandibular ramus from Brazil in the British 
Museum (No. 18649 a), 
