FOSSIL VA RA NID AE AND ME O ALA NID AE. 
861 
1 ° the. de scription of 1889 contains a detailed enumeration of the morpho¬ 
logical markings, being accompanied by a figure, which however, as men¬ 
tioned above, is very vague ; the publication of 1900 on the other hand, gives 
no description of the teeth, but annexed to it we find most fine and cons¬ 
cientious drawings, The figures of 1889 and 1900 thus differ a good deal from 
eachother (Textfigs. 15 & 16), and do not offer sufficient guarantee for specific 
determination or identification; the description (of 1889) alludes to 
many characters equally recognizable on the later drawing (of 1900), never¬ 
theless excluding even thus an absolutely certain systematical determina¬ 
tion, since some markings, as for instance the development of an «acute 
caudal edge», are not traceable on the laterally-vie wed figures. Further¬ 
more a determination based on literary references would in this case prove 
impossible by the fact of the characters (curvature, serration) enumerated 
by pe Vis often occurring in different species where they show 
but relatively slight modifications. 2° The tooth figured in 1887 is deci¬ 
dedly 1 a r g e r and — as far as may be detected from the figures — 
appears robuster than those represented in 1900. — Having set forth in 
the above all the reasons causing my doubts, I note in the following 
three eventualities which may be foreseen, as far as is possible to judge 
so delicate a matter at such a distance. 
1° That Mr. de Vis’ determination is right, the two different 
remains belonging to the same species. 
2° That the tooth first described is that of a smaller individual of 
Megalania (— Notiosaurus) the generic (and familiar) determination 
«Varanus» being thus wrong. 
8° That both remains, the single tooth and the dentigerous maxillary, 
are Yaranian, though belonging to two different species, the latter fragment 
maybe to the second described V. emeritus. 
Another question arises as to the reason which may have induced 
Mr. de Vis to unite the small, undescribed femur with the tooth under 
the name of V. dirus and the equally smaller tibia with the humerus as 
representatives of another species: V. emeritus. What circumstances may 
have prompted him to separate these four remains just 
in this m a n n e r, and what led him to separate these Yaranian 
fossils precisely into the two species established by 
him? Mr. de Yis’ papers contain no clew to these questions. 
Thus both, V. dirus as well as V. emeritus , might prove of good spe» 
cific evidence, or might also represent a so-called «mixed species»; at all 
events a thorough revision of the questionis required. For the present, both 
must at any rate, be regarded as of very problematic s y s t e- 
