ON NORTH AMERICAN ZOOLOGY. 



199 



alligator luciiis or Mississippiensis, which attains the 32^'' N. 

 latitude, and in Georgia and Carolina winters in burrows. 

 The ophidla swarm in the humid equatorial districts of Ame- 

 rica, but disappear on the acclivities of the Cordilleras, at 

 an altitude of 6000 feet, and a mean annual temperature of 

 64° F. In the fur countries they reach the 55th parallel where 

 the mean heat is about the freezing point, but where the tem- 

 perature of the three summer months, during which only the 

 serpents are visible, is at least 66° F. and very little inferior to 

 the summer heat of the Mexican table lands. In Europe the 

 isothermal line of 32° passes through the North Cape (lat. 71° 

 lOV N.), and we find accordingly that some serpents (as the 

 coluber berus) reach Norway. In like manner lizards {lacerta 

 ocellata) exist in Kamtschatka and Sweden, though none of the 

 saurians pass to the north of the 50th parallel in America. The 

 following is a list of the genera of European and Egyptian rep- 

 tiles, with the number of species noticed in Mr. Gray's synop- 

 sis, or the R^gne a7iimalgiven for the purpose of comparison with 

 the subjoined table of North American ones. European rep- 

 tiles : Chelonia. — Testudo 2 ; cistudo 1 ; emys 1 ; trionyx 1 ; 

 sphargis 3. Emydosauri. — Crocodili 2. Saurii. — Monitor 2 ; 

 lacerta 14; psammodromus 1 ; algyra 1. Geckotidce, — Platy- 

 dactylus 2 ; stenodactylus 1 ; thecodactylus 2 ; hemidactylus 2. 

 Iguanidce. — Agamae 6. Sciiicidce. — Scincus 1 ; tiliqua 2 ; 

 anguis 1. Zonuridce. — Ophiosaurus 1. Ophidia. — Trigonoce- 

 phalus 2 ; vipera 1 ; berus 2 ; pelias 1 ; echis 1 ; naia 1 ; tro- 

 pidonotus 5; coluber 6; coronella 3; dendrophis 1. 



Obs. — The following list of American rep f ilia is compiled 

 chiefly from Mr. Gray's synopsis in Griffith's translation of 

 Cuvier, and will appear meagre and inaccurate after the publi- 

 cation of Wiegmann's and Holbrook's works. Species which do 

 not range north of Mexico are in Italics. 



Ord. I. CHELONIA. 



Fam. Testudinid^. 

 Testudo polyphemus, Bartr. 18. 



Fam. Emyd^. 



Cistudo Carolina, Holb. 1. 

 Emys Muhlenbergii, Id. 5. 



„ guttata, ScHCEPF. 31. 



„ iHiiictiita, Holb. 4. 



,, iiicta, ScHCEPF. 5, 



I, speciosa, Id. 



Emys concentrica, Schcepf. 15. 



„ reticularia, Daud. 23, 3. 



„ vittata, 



„ decussata, 



„ scripta, Schcepf. 3, 5. 



„ serrata, 



„ rugosa, 



„ Troostii, Holb. 4. 



,, Le Sueiuii, Gray. 

 Kinosternon triporcatum, Wieg. 15. Mex. 



„ seorpioides, Shaw, 15. Me.v. 



„ pennsylvanicum, Edw. 287. 



,, odoratum, Daud. 24, 3. 

 Chelydia serpentina, Schcepf. 6. 



