512 SNAKES OF THE GENUS LICHANURA STEJNEGER. 



The comparative large size of the eye in L. trivirgata, coupled with 

 the very pronounced i^attern of coloration, might tempt one to regard 

 it as the young of one or another of the forms since described, but the 

 fact that the second specimen (U. S. Nat. Mus., No. 12602), although 

 very much larger than the smallest of the other forms, in color and 

 size of eye agrees completely with the type (No. 15502) — a very young 

 individual — seems to prove the distinctness of this species, which has 

 so far been found only at the southern extremity of the Lower Califor- 

 nian peninsula. The low number of gastrosteges may also be a char- 

 acter of this species. 



In addition to this larger size of the eye L. trivirgata shows a very 

 pronounced difference in coloration from the forms collected farther 

 north, it being creamy white, with three broad and abruptly defined 

 blackish-brown longitudinal bands, while the others are either entirely 

 uniform above, or with only faint indication of brownish zigzag bands on 

 a bluish ground. Both specimens of this form at hand are identical in 

 this respect, although of very unequal size, and judging from the origi- 

 nal description the only other specimens of this species recorded — at 

 least two (see Proc. Phila. Acad., 1861, p. 304) — were of the same well- 

 marked pattern. 



The same reason which prevented us from regarding the largeness of 

 the eye as due to young age, operates against explaining the distinct j 

 color pattern as a sign of immaturity, for the type of L. myriolepis m\ 

 considerably smaller than Beldiug's specimen of L. trivirgata, and yet 

 it is not more distinctly marked than all the other specimens found to 

 the north. 



As far as scutellation is concerned it may at once be stated that L. 

 trivirgata shows no character (with one possible exception) by which it; 

 can be separated from the forms described as L. myriolepis, roseofusca^ 

 and simplex. The extent of the variability in these forms may bej 

 gathered from a glance at the table of specimens given below, to sup- 

 plement which I may use the same words in which I characterized a j 

 similar condition in Charina (Proc. U. S. Nat. Mus., xiii, 1890, p. 179), ' 

 viz, "there are no two specimens alike," and " there is hardly an indi- 

 vidual with both halves of the head alike." 



The possible exception referred to above is the low number of gas-j 

 trosteges (218); but in view of the extent of variation in this respect 

 among the other specimens (224 to 241) this character can hardly bej 

 expected to hold. 



As to the forms trom " northern Lower California," collected by Gabb,l 

 and those from southern Upper California, the inspection of the type] 

 specimens of L. myriolepis and roseofusca has simplified matters con- 

 siderably. The former is a specimen of comparatively small size, but] 

 fairly well preserved ; the latter is a skin in alcohol of a large Individ- 1 

 ual and in a very bad shape. To this unfortunate circumstance is 

 undoubtedly due the inaccuracies and incompleteness of the original 



