10 SWED. ZOOL. EXP. TO SIAM, EINAR LÖNNBERG. 2. LIZARDS. 



Isopachys n. g. 



Body cylindrical, a little depressed in front, not tapering towards the posterior 

 end which is abruptly rounded off. Limbs absent. Scales smooth with thin, under- 

 lying osteodermal plates of the usual appearance with symmetrical tubules. Nostril 

 pierced in a large nasal, no supranasal. Tongue rather thin and free in front, covered 

 with imbricate scale-like papillse. Teeth in the jaws rather stout with blunt cusps. 

 Pålat ine bones separated in the median line. No tympanum. Eyes rudimentary. 

 Frontoparietals double, interparietal distinct. 



22. Isopachys gyldenstolpei 1 n. sp. 



Head short, triangulär, but rather broadly rounded of in front (conf. fig. 3), 

 the musculature of the jaws giving it a somewhat swollen appearance. (Unfortunately 

 the head has been somewhat damaged by a blow and therefore some details of the 

 structure cannot be exactly described. These have also been left out in the figures 

 which are so carefully represented as possible.) The obtusely rounded snout projects 



Fig. 2. Isopachys gyldenstolpei Fig. 3. Isopachys gyhlenstol)» i 



(twice enlarged). (twice enlarged). 



A. österberg del. 



beyond the end of the lower jaw. The rostral is very large and forms on the upper 

 side of the snout an almost straight suture with the large nasals which broadly meet 

 in the median line. They form in the corner between the rostral and the first labial 

 an almost right angle and there at some distance from the anterior margin and a 

 little further from the lower the nostril is pierced. Wcdged in between the large 

 nasals are to be secn the remains of a shield but whether this represents a fronto- 

 aasal, or the anterior end of a ver)' large frontal cannot be decided as it is broken. 

 The posterior end of the frontal is wedged in between a pair of elongate fronto- 

 parietals, but is at the posterior end in contact with the anterior end of the inter- 

 parietal; latter shield longer than broad mucfa smaller thau the frontoparietals. 

 Parietals large, meeting behind the interparietal to form a long oblique suture. The 

 posterior margin of both parietals is bordered by a row of five strongly enlarged 

 auchal scales which, however, are not equal inter se. Even some scales behind these, 



1 Named for Coant Nn.s Gtldenstolpe who haa made two Buccessful expeditions to Siarn and greatly 

 contribated to the knowledge aboal tlit- vertebrate fanna of that country, 



