Allen.] 174 [December 2, 



by him communicated to the IMnscum of Comparative Zoology. 

 The chief additions, then, to the species given in Dr. Storer's 

 Report, arc the Sco!ophis al!e(jlianieiit!l>!, Atwistroilon contorlrix and 

 Scapliiopus Ilolbrooldl. The only other species likely to exist is 

 the Terrapin (j\IalacocIe7rmii/s pahislri.^:), which from its occmTcnce 

 in Connecticut and Rhode Island we expect will ultimately be found 

 in Massachusetts. 



In reference to the geographical distrilHition of the Reptiles and 

 Batrachians of Massachusetts, the data are as yet too few to deter- 

 mine positively whether two faunaa can be clearly distinguished, — the 

 Canadian in the western, embracing the mountainous districts, and 

 the Alleghanian in the eastern, embracing the lowlands, — as in the 

 case of the mammals and birds; though from what is known of the 

 general distribution of these animals this seems probable, and that the 

 line of separation between the districts nearly coincides with that for 

 the mammals and birds. Considered in connection with those inhab- 

 itating the adjoining regions, it is evident that in the case of some of 

 the acpiatic species, other physical conditions than temperature exert 

 a powerful intluence in determining the limits of their distribution. 

 Thus in the State of New York there seem to be three taunas as dis- 

 tinctly as there are two in Massachusetts — the Canadian at the north 

 and in the mountains, the Alleghanian in the lowlands, and, in addi- 

 tion, for these classes at least, what may he termed a Huronian, lying 

 west of the great Appalachian watershed, and characterized by the 

 occuiTcnce of several species of Chelonians and Urodela not found to 

 the eastward; corresponding also to the ''Great Lake Fauna" for 

 fishes, and to which Lake Champlain probably belongs, as Mr. Put- 

 nam has noticed.! 



Massachu.setts is quite too far north to furnish many species of Sau- 

 rians, the existence here of the single one thus far discovered resting, 

 so far as I can learn, on the capture of the solitary example recorded 

 by Dr. Storer. It is a species, however, whose habitat nearly reaches 

 to Massachusetts, since it occurs not unfrequently, as well as another 

 species, in the southern counties of New York, and in the extreme 

 southern parts of Connecticut. Massachusetts is also near the north- 

 ern limit of distribution of the Testudinata, some sjoecies apparently 

 not reaching the highlands of the State, while a few only pass north- 

 ward of the lowlands of southern Maine, or into the Canadian Fauna. 

 None occur to the northward that do not ailso occur here, while the 



» Proc. Bost. Soc. Nat. Hist., Vol. IX, pp. 178 aud 233. 



