Occasional Papers of the Museum of Zoology ^ 



riorly on the belly there is, as in the type, a single large black blotch 

 opposite each of the dorsal whitish bands. Posteriorly, however, 

 these blotches become irregular and the black pigment is much 

 increased in amount. Whatever this specimen is, it is not a trian- 

 guliim. It may represent a derivative of iriangulum as yet unrec- 

 ognized, but in view of the great variability exhibited by specimens 

 from the Middle Atlantic region and the lack of representatives 

 from large areas of Virginia, Delaware, and Maryland it is not 

 possible at present to define the characters of this unknown form or 

 even to be certain that such a form exists. The present plan of 

 identifying this aberrant specimen as virginiana is admittedly an 

 expedient for delaying the settlement of the difficulty until more 

 specimens shall be available for study. The dentition of this 

 individual, except for the pterygoid teeth, is as follows: maxil- 

 laries, 13; mandibulars, 13; palatines, 11. 



The specimen in the Academy of Natural Sciences of Phila- 

 delphia (No. 3601) is of uncertain origin. It may be from Dela- 

 ware. It is closely similar to the Cuscowilla specimen and is with 

 little doubt a virginiana. 



The form virginiana, as defined by the tj'pe and represented by 

 all the others listed except the two doubtful ones (those from 

 Alberene and the District of Columbia), is without doubt a deriva- 

 tive of elapsoides by an alteration of the pattern closely similar to 

 that which took place when the subspecies of triangulum changed 

 from the ringed to the saddled type of pattern. Whether this 

 change toward the triangulum type went so far that individuals of 

 virginiana were able to hybridize with the degenerating section of 

 triangulum of the Middle Atlantic states seems improbable. It is 

 more likely, as indicated above, that there exists in this region a 

 degenerate derivative of triangulum. This question can be 

 settled only when specimens shall be available from the Delaware- 

 Maryland peninsula and from eastern Virginia. 



