46 REPTILES". 



if we may so express it, they are Seps without feet; they are all com- 

 prised in the genus 



Anguis, Lin. 



The Blind Worms, which are characterized externally by imbricated scales, 

 with which they are completely enveloped. They have been separated 

 into four subgenera; in the three first we still find beneath the skin the 

 bones of the shoulder and pelvis. 



Pseudopus, Merr. 



Have the tympanum visible externally, and on each side of the anus a 

 small prominence* which contains a little bone analogous to the femur, 

 connected with a true pelvis concealed under the skin. As to the anterior 

 extremity it hardly shows itself externally, its only mark being a fold not 

 easily detected; it has no internal humerus. One of its lungs is a fourth 

 less than the other. The scales are square, thick, and semi-imbricate, 

 some of which, between those on the back and those on the belly, being 

 smaller, occasion a longitudinal furrow on each side. 



Pallas has described a species of the south of Russia, which is 



also found in Hungary, and in Dalmatia; the P. Pallasii, Nob.; 



Lacerta apoda, Pall. Nov. Com. Petrop. XIX, pi. ix, f. 1 ; from 



twelve inches to two feet in length ; scales on the back smooth ; 



those on the tail carinated. 



M. Durville has discovered another in the Archipelago, Ps. Dur- 



villii, Cuv., whose dorsal scales are rough and carinate like those on 



the tail. The 



Ophisaurusj, Baud. 



The Lizard Serpents only differ from the preceding subgenus in the 

 entire deficiency of any external appearance of posterior extremities ; the 

 tympanum, however, is still visible, and the scales also form a fold on each 

 side of the body. The small lung is one-third as large as the other. 



The most antiently known species, Oph,. ventralis ; Ang. vcntralis, 

 L., Catesb. II, lix, is common in the United States. It is of a yel- 

 lowish-green, spotted with black above; the tail is longer than the 

 body, and is so easily broken, that it is commonly termed the Glass- 

 Snake J. 



Anguis, Cuv. 



The Blind Worms, properly so called, have no external appearance 

 whatever of an extremity; the tympanum even being concealed under the 

 skin ; the maxillary teeth compressed and hooked, and none in the palate. 

 The body is surrounded with imbricated scales, but has no fold on the 

 side. One of the lungs half the size of the other. 



* Pseudopus, i. e. false foot. I have never been able to discover any division of 

 the extremity of this very small vestige of a foot. M. Schneider has been equally 

 unsuccessful. 



■f From the Greek words, ophis, a Serpent, and sauros, a Lizard. 



}' Add Ophis punctatus ; Oph, slriatulus, Nob.; two new species. 



