Zoology.-] NATURAL HISTORY OF VICTORIA. [Heptilia. 



Plate 102. 



TRACIIYDOSAURUS RUGOSUS (Gray). 

 The Rugged Stump-tail, or Shingle-back, Lizard. 



[Genus TRACIIYDOSAURUS (Gray). (Sub-kingd. Vertebrata. Class Reptilia. Order 

 Suuria. Sub-order Leptoglossae. Tribe Geissosaura. Earn. Scincidae.) 



Gen. Char. — Form moderately elongate, thick, fusiform ; tail very short, broad, depi"essed. 

 Head large, trigonal, pointed in front ; neck very sliort, narrow (head shields, ears, palate, 

 tongue, body, and limbs as in Oyclodus) ; teeth blunt, conical ; scales of back very large, very 

 thick, bony, with a rugged, ridged surface.] 



Description. — Form: Sliort, rounded, moderately depressed, sides rounded; 

 head very thick, trigonal, obtusely pointed in front, widening- to ear behind; neck 

 short, moderately constricted ; back sloped from midline on each side ; tail very short, 

 depressed, slightly rounded above, flat below, little narrower than the body, ending 

 in a small, conical tubercle ; anterior and posterior feet nearly equal ; toes very short, 

 and only slightly different in length, middle one longest, then 2nd, then 4th (a 

 little shorter than the 1st), then the 5th on anterior foot; three first toes gradually 

 longer, 4th shorter than 3rd, 5th shortest on hind foot. Scales : Nasal plates very 

 large, meeting over top of rostral;* inter-nasal hexagonal, very slightly wider than 

 long ; two fronto-nasals pentagonal, touching by their inner edges; frontal hexagonal 

 small, slightly longer than wide; five supraoculars; eyelids scaly; a curved row of 

 seven suboculars ; two fronto-parietals small, hexagonal, joining by inner edges; 

 inter-parietal hexagonal or heptagonal, little larger than frontal ;f two parietals 

 heptagonal, little larger than inter-parietal; behind parietals and occiput are four 

 rows of thick, rugged scales like those of neck ; two fronto -orbital plates on each side 

 and two frcenals ; ear moderately open, with simple margins ; scales of back very 

 large, thick, sub-rhomboidal, with numerous, coarse, irregular ridges converging 

 towards middle of posterior edge, those of middle of back largest, having two 

 rows, those of sides forming oblique bands, those of tail with one median large keel 

 ending in a point at the posterior edge; all the lower surface of chest, abdomen, 

 and tail covered with thin, smooth, wide, hexagonal plates. Color : Upper surface 

 dark rich Vandyke-brown, with transverse, irregular, paler yellowish-brown bands, 

 forming usually eight or nine transverse, irregular chevrons from neck to tip of 

 tail, one to two scales wide, above irregularly spotted at tip of scales with rich 

 blackish-brown; the intervening, dark spaces two or three scales wide; on under- 

 side the color is yellowish- white, irregularly blotched and mottled with dark brown. 

 The coloring varies considerably; one specimen in the collection being entirely dark 

 brown above, with only one light transverse band, five scales wide, behind the 

 shoulder, and nearly uniform brown below ; another is transversely banded on belly 

 and under-side of tail, much as on the back ; while in another the dark marks below 

 are chiefly longitudinal blotches. Tongue flat, wide, notched at the tip, blackish- 

 purple; inside of mouth pinkish-white. 



* In some specimens the nasals do not touch, bnt the rostral and Inter-nasal touch. 

 t In some specimens smaller, and tin> Length ami width equal. 



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