Horváth Géza (szerk.): A Magyar Természettudományi Múzeum évkönyve 16. (Budapest 1918)

Fejérváry, G.J.: Contributions to a Monography on fossil Varanidae and on Megalanidae 16

senting a large subtriangular surface, the lower angle of which indicates the place where the missing first hypapophysis had risen. About 2 mm under the articular ball a large subrotund surface indicates the traces of the broken «t a 1 o n» which had to support the second hypapophysis

1 missing on the fossil. On both sides of the centre, nearly at the limit between this latter and the neural arch, two small bony ridges may be observed faintly rising in the vicinity of the middle region of centre and terminating in a somewhat swollen proëmiirence which cannot be more precisely examined, being broken together with the odontoid process, closely before the limit of which the mentioned elevations must have reached their strongest development. I stated the presence of homologue ridges under the form of small spines on the epistropheus of Varanus griseus DAUD. These spines to which I give the name of Spinae t r a n s v e r s a e are present also in other L a c e r t i 1 i a n s, all hough I was not able to find any allusion made to this fact in the anatomical literature consulted on the subject. The question arises, whether these spinœ transversa? are not rudiments of the second vertebra s earlier proc. transversi, having degenerated by fusion with the centre of the atlas, and being actually reduced to a most inconspicuous rudimentum. In that case, the spinse transversa? ought to be homologous, or even nearly homotype with the processus transversi. Neural arch rather narrow, widening backwards and forming the well developed, massive but narrow proc. obi. posteriores. The anterior zygapophyses are broken. Of the posterior ones, just referred to, that on the right side is complete, whilst the left one is missing ; the lower (articulating) surface is convex, blunt ; the outer surface presenting a larger triangle whilst 1 he i n n e r, just opposed to it, forms a smaller and more pointed one; the hind (upper) surface presents an elongate parallelogram whose inner side continues into the base of the large subtriangular surface formed by the hind part of proc. spinosus. The moderately prominent edge separating the o u t e r and the lower (articulating) surface of proc. obi. post, begins by a very faint keel about the middle region of the horizontal outline of the neural arch. Processus spinosus severely damaged, the whole anterior part of it being broken, SO that, laterally viewed, an arch is seen instead of the tectiform out1 In Varanus also the hypapophyses (and the [caudal] ha e m a po p h y s e s) are only attached t o the talon of their own centre, thus confirming the statement of SIEBENROCK, LEYDIG and HOFFMANN (SIEBENROCK, Skelet d. Lac. Simonyi u. d. Licertidenf. übcrh., Sitzungsher. kais. Akad. Wiss. Wien, Math. Naturw. Cl., Bd. CHI, Abth. I, 1894, p. 263) and refuting the opinion of Sir R. OWEN and CEGENBAUR, according to whom the chevron-bones ought to be of an interVI rtrebra] position (SIEBENROCK, 1. c).