Jávorka Sándor - Soós Lajos (szerk.): A Magyar Természettudományi Múzeum évkönyve 29. (Budapest 1935)

Fejérváry, G. J.: Further contributions to a monograph of the Megalanidae and fossil Varanidae - with notes on recent Varanians

sided evolutionary dependency of one character on another.'

4 After this remark bearing upon the biomechanically determined development of the Megalanian ostoses here dealt with and of their antagonistic hollownesses, I wish to point to the conclusion I draw from all evidences concerned: The ostoses at stake are epistatic or iments of zygosphenes, what means that the zygosphenes of Megalania are fixed in a phase of paracmic evolution, i. e. they are in a state of paracmic e p i s t a s y. And the same obtains, of course, for the shallow impressions on the caudad surface of the neural arch, interpreted by me, in my Monograph, as zygantra. thus, though on the ione hand accepting without reservation Mr. LONGMAN'S opinion that I was mistaken in stating Megalania to possess ,,strongly developed" zygosphenes and zygantra, I am compelled on the other to positively state, under the weight of compulsory evidences, that the homologization of the features in question as zygosphenes and zygantra, objected to by the eminent Australian Zoologist, proves to be practically correct. It is absolutely impossible to acknowledge that the „small lateral tubercles" given off by the „small and irregular area above the neural canal on the anterior side" are to be regarded, with respect to their homology, as outgrowths belonging to a recess .,mainly composed of the anterior ridge of the neural spine." A processus praespinalis (F.-LGH., 1923) as described by HILGENBORF

55 in Ophisaurus moguntinus BTTG. (= Propseudopus Fraapi ] LILG.) and by Baroness DE FEJÉRVÁRY-LÁNGH

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5 in O. moguntinus, 54 I care to observe that I consequently adhere to Prof. DÜRKEN'S terminology hearing upon what I whish to designate as the aetiognosy and nomognosy of the organic features' individual and ultra-individual, i. e. euthygenetical and phylogenetical, evolution. If characters be bionomically examined and parallelled from the view-point of organic mechanics, we may distinguish, according to DÜRKEN, three main types oi their co-occurrence: 1° the relation, consisting in a one sided evolutionary dependency of a character from another; 2 " the correlation, which is the mutual biomechanical affect directly produced by the parts or organs at stake (functional interaffect, reciprocate irritalion, determining individual and ultra-individual mode of development, either ,.growth" or decrease) : 3° the combination, consisting in a functionally and, thus, morphogenetically so to say ..independent" co-existence of the featuies bionomically (i. e. aetiognostically and nomognostically) analysed with respect to the fact of their simultaneous presence in the organism dealt with. (Cfr. B. DÜRKEN, Einführung in d. Experimentalzool., Berlin, 1919, p. 129). 55 Die Steinheimer Gürteleidechse Propseudopus Fraasii, Zeitschr. d. Deutsch. Geol. Ces.,XXXVH, 1885, pp. 358-578, Taf. XY-XVI. Op. cit. p. 175 & 211, Taf. Ill, Fig. 4. Tai. IV, A: Fig. 16 (process markeel ,.z"). .