PITUOPHIS WILKESI. 137 



2. PITUOPHIS WILKESI, B. & G. 

 (Plate IX, figs. 1-7.) 



CHAR. SPEC. Scuds postfrontalibus in dua paria disposiiis. Squamis 

 dorsualibiis in 2931 series lonyitudimtles ordinatis ; tribus seriebus 

 externis laevibus. Cauda circiter sextain longitudinis partem efficiente. 

 Vitta postoculari, super ultimam labialem, usque ad oris angulum 

 2'i'otensa. Colore flavido, dorsuali serie subquadratorum et duabus 

 lateraUbus seriebus subcircularum fuscarum macularum, notato. 



SPEC. CHAR. Two pairs of postfrontal plates. Dorsal series of scales, 

 twenty-nine to thirty-one; the three outer series smooth. Tail about 

 the sixth of total length. Postocular vitta running over the last 

 labial to the angle of the mouth. Ground color yellowish, with a 

 dorsal series of subquadrate, and two lateral series of siibcircular 

 blotches. 



Z^y.Pituophis wilkesii, B. & G. Catal. X. Amer. Kept. I, 1853, 71. 



DESCR. The head is elongated, subelliptical, subpyramidal or sub- 

 conical. The occipital plates are much longer than broad, and longer 

 than either the vertex or the supraoculars. The vertex plate is penta- 

 gonal, laterally concave, and posteriorly tapering; its length is greater 

 than the width of its anterior margin. The external postfrontals are 

 sometimes divided into two distinct plates, one of which having been 

 called upper loral. The internal postfrontals are elongated, very 

 narrow posteriorly, sometimes subdivided also. The rostral is broad, 

 superiorly rounded and not engaged between the prefrontals. The 

 nasals are of equal size, with the nostril intermediate, and situated 

 nearer the frontal than the labials. The loral is of moderate develop- 

 ment. The lower anteorbital is small, and situated upon the com- 

 missure between the fourth and fifth upper labials. The postorbitals 

 are nearly of equal size, and generally they constitute a continuous 

 chain with the anteorbitals, thus excluding the labials from the orbit, 

 into which, however, the fifth occasionally enters. The temporal 

 shields are scarcely distinguishable from the ordinary scales. The 

 upper labials are eight or nine in number; the fourth or fifth oc- 

 casionally entering into the orbit, the penultimate being the largest. 



35 



