330 



BULLETIN 58, UNITED STATES NATIONAL MUSEUM. 



instead there are numerous more or less complete narrow, dusky, 

 transverse zigzag lines often with pale edges, or these cross lines are 

 interrupted so as to form a lateral series of dots and a dorsal cross 

 line, often (|uite oblif[ue; on the posterior half of the upper surface 

 of the head there is a brown, black-edged pattern somewhat resem- 

 bling an ornate M , and anterior to this a semilunar band across pre- 

 frontals and supraoculars, as well as various marks of similar color 

 on top and sides of the snout and on the supralabials ; a brown black- 

 edge postocular band crossing the last supralabial; ventrals faintly 

 marked with brownish except on lateral angle which is visible as a 

 wliitish line. 



Variation. — The number of scale rows and of supralabials seem to 

 be absolutely constant in this s]:)ecies, and only two aberrations with 

 regard to the latter are on record, namely, two specimens examined 

 by Doctor Wall, who in one found on one side three supralabials 



283 



Figs. 2S2-283.— Elaphe ijuadrivirgata, young. Enlarged. 282, color pattern of top of head 



AND neck; 2a3, COLOR PATTERN AROUND THE MIDDLE OF THE BODY. No. 2343.'), U.S.N.M. 



entering the eye instead of two and in another 9 supralabials on 

 one side, fifth and sixth touching the eye. An undivided anal occurs 

 sometimes, and curiously enough it is found in no less than three 

 specimens out of the five on record from Shikoku (Nos. 81876-31878). 

 The subpreocular is also occasionally wanting, sometimes on both 

 sides. Doctor Hilgendorf found three postoculars only once on one 

 side, while several in our series show this anomaly, thus Nos. 23434 

 and 23435, while No. 4677 has them on both sides. The normal 

 number of temporals is 2 + 2, but about 35 per cent of the specimens 

 examined by me have 2 + 3, while I have only found 1 + 2 in three 

 specimens, namely, Nos. 33978, 33979, and 34016. The number of 

 ventrals varies between 193 and 215, subcaudals between 70 and 99. 

 The coloration is very varial^le. In the first place, there are two 

 distinct color phases, the normal pale one with the distinct four stripes, 

 the other a melanistic phase, more or less uniform blackish brown 

 with the stripes more or less obscured according to the darkness of the 



