636 REPORT OF NATIONAL MUSEUM, 1898. 



are completely concealed or sometimes more or less blunted, contracted, 

 or obliterated. With the disappearance of the cephalic stripes the 

 median dorsal first becomes obscure; the ground color changes from 

 black or narrow dorsal olive stripes to predominant light olivaceous. 

 For a considerable time the black on the sides remains distinct and 

 continuous, but ultimately is reduced to dusky margins to the scales. 

 Sometimes the lateral whitish stripes disaj^pear or are very obsolete, 

 the black stripe remaining distinct; or the reverse maybe the case. 

 The lateral light lines are, however, quite late to disappear entirely. 

 There is often a trace of the original black above in a line of dusky 

 dots down the middle of the two dorsal rows of scales, and that of the 

 third or fourth row from the central line of the back, formerly continu- 

 ous stripes bordering the white. By degrees the lateral stripes become 

 more and more obsolete, until there is only the faintest trace or they 

 have disappeared entirely, leaving the body of a uniform greenish or 

 reddish olive above and a light brick-red head as broad as long. The 

 lowest lateral white stripe can usually be detected on oldest specimens 

 as well as some of the dusky of the sides ; the scales of the back, how- 

 ever, become entirely uniform. 



In Cat. No. 4136 there is a distinct whitish stripe between the legs 

 below what is ordinarily the lowest, making three on each side, the dor- 

 sal wanting. This is seen more or less distinctly in other specimens, as 

 Gat. No. 3178, th6ugh usually wanting. The various changes described 

 do not apj)ear to progress uniformly in all specimens. Sometimes a 

 series of specimens of the same size will exhibit all the stages, except 

 the earliest. 



Professor Baird has shown that the Scincus erythrocephalus, quinque- 

 lineatus, and fasciatus are forms of the same species, the first name 

 having been given to old males. 



From the preceding remarks it will be seen that I have adopted his 

 opinion, combining in one all the three species described by Dr. Hol- 

 brook as inhabiting the United States. This I have only done after a 

 protracted examination of a large series of specimens from all parts of 

 the United States. I have failed to find any constant distinctions in 

 the external structure and relative proportions, while the differences 

 of coloration are only those readily attributable to age and sex. It is 

 well known that the characteristic markings of the skinks are most 

 appreciable in the young. Now, in the present case none except the 

 very largest have the coloration of erythrocephalus, none except the 

 middle and the largest size (females) that of qiiinquelineatus, while every 

 one before me with a head and body of less than 2 or 2i inches agrees 

 exactly in coloration with the most typical fasciatus. To sum up the 

 whole case, I feel very confident that the three (or four, including Dr. 

 Hallowell's P. vittigerum?) supposed species in reality constitute but 

 one; that the species attains a much larger size in the more Southern 

 States than the Northern, there going through all the stages of colora- 



