434 
G. J. DE FEJÉR VARY 
CHAPTER IV. THE DESCENT AND PHYLETICAL RELATIONS 
OF VARANIDÆ. 
The descent of Varanidae, despite comparatively numerous and 
careful researches on the question, — amongst which, as most important, 
may be cited Baur. Boulenger, Osborn, Williston, Fürbringer and 
Nopcsa’s valuable works, — is yet concealed by a veil of darkness ; for, as 
regards the Varanidae, these eminent investigators only point to 
phyletical relationship, whilst the orthogenetical 
connexions have remained up to this day in absolute uncer¬ 
tain t y. Besides the suborder Platynota, Mosasauria has for the present 
been inscribed in the system as an especial suborder. According to Boulen¬ 
ger 1 Mosasauria derive their origin together with the Varanoids 
from the Dolichosauria 2 Baur 3 does not accept this opinion, qualifying 
Mosasauria as «highly specialized aquatic forms» «closely related to the 
Varanidae » (fide Nopcsa), for which reason this group alluded to 
under the name of Mosasauridae is judged by him as merely 
occupying the rank of a family. Nopcsa endeavours, to the 
satisfaction of both parties, to settle the litigious points separating 
Boulenger and Baur in this subject, and concludes to the fact 
of the Dolichosauridae not being ancestral «to any of the larger groups of 
Squamata»; Nopcsa therefore draws a distinct limit between the Dolicho- 
and Aigialosauridae ; with regard to M o s a s a u r s he refers the phylo- 
genetical point of departure, which Baur — contrarily to Boulenger — 
denied in connexion with Dolichosauria, to the Aigiatosauridae, by which 
Boulenger’s opinion, — by whom however the two groups were not yet 
distinguished — gained in prevalence. Baur and Boulenger, both agree 
to the fact of the Varanidae being immediately related to 
Mosasaurs. As mentioned before, Nopcsa considers the Aigialsauridae 
as the more ancient group, 4 and distinctly separates them from the Dolicho¬ 
sauridae. In the mean time he wishes to prove that Mosasaurs 
1 Cretaceous Lizards and Bhynchocephalians, Ann. & Mag. for Nat. Hist., Lon¬ 
don 1893. 
2 The striking differences stated by Nopcsa between the Dolichosauridae and 
the Aigialosauridae had then not yet been established. — See Nopcsa : On the Origin 
of the Mosasaurs, Geol. Mag., Decade IV, Voi. X, London, 1903., p. 119 — 121; Über 
varanusartige Lacerten Istriens, Beitr. z. Pal. u. Geo]. Öst.-Ung., Bd. XV, Wien u. 
Leipzig, 1903, p. 31—42, & op. cit. 
3 Morphology of the' skull of Mosagauridæ, Journ. of Morph., Vol. XII, 1892. 
(Quoted from Broili [op. cit.]). 
4 Opera citata. 
