GIGA^’TOrillS GAESTINI. 
307 
Genus GIGANTOPHIS, Andrews. 
[Geol. Mag. [4] vol. viii. (1901) [). 438.] 
This genus includes very large snakes, distinguished from the recent Pythons in 
having vertebric in which the neural spine is less developed and the articular surfaces 
of the zygosphene and prezygapophyses and of the zygantrum and the postzygapophyses 
respectively are nearly parallel with one another. 
Gigailtopllis garstini, Andrews. 
[Plate XXVI. figs. 1-3.] 
1901. Gigantoplds garstini, G. W. Andrews, Geol. Mag. [4] vol. viii. p. 438, fig. 1. 
Tjjpe Specimen . — A series of about twenty associated vertebrse, with some fragments 
of ribs (PI. XXVI. fig. 1) ; Geological Museum, Cairo. 
The type and only known species, distinguished by its large size, it having attained 
a length of about thirty feet (rather more than 9 metres), if the proportions of the 
vertebrae compared with the length of the body were as in Python molurus. 
Form. & Log. — Qasr-el-Sagha beds (Middle Eocene) : north of Birket-el-Qurun. 
Pemains of this large Ophidian are very common in the Qasr-el-Sagha beds, 
occurring usually as isolated and much-weathered vertebree. In the type specimen 
the vertebrae remain united in groups, one of which is figured on PL XXVI. fig. 1. 
These vertebrae are closely similar to those of Python, the chief differences being that 
the neural spine is less developed, being confined to the posterior part of the arch, 
and that the planes of the articular surfaces of the zygosphene and prezygapophyses 
and of the zygantrum and postzygapophyses respectively are more nearly parallel 
with one another. 
In the procoelous centrum the transverse diameter of the anterior cup is slightly 
longer than the vertical one; the posterior ball is of corresponding form, and looks a 
little upwards instead of directly backwards ; on the posterior half of the ventral surface 
there is a low, blunt, hypapophysial ridge [Ityp.). The neural arch is extremely 
massive, and on its posterior half it bears a small, stout, neural spine (n.sp.). The 
anterior zygapophyses {a.z.) form strong prominences, continuous below Avith the 
transverse processes ; their articular surfaces are roughly triangular in outline, and 
look rather more inw'ards than in Python, in which they are nearly horizontal. The 
zygosphene {zs.) is a greatly thickened prominence, the articular facets of which look 
outw’ards and downw’ards and are nearly parallel with the surfaces of the anterior 
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