KEVISIOIs^ OF THE KING SNAKES. 221 



LAMPROPELTIS RUTHVENI Blanchard. 



Fig. 74. 



1920. Lampropeltis ruthveni Blanchard, Occ. Pap., Univ. Mich., no. 81, p. 8, 

 pi. 1, fig. 2 (type locality, Patzcuaro, Michoacan, Mexico; type specimen, 

 U. S. Nat. Mus., no. 46558; collected by E. W. Nelson, Aug. 2, 1892). 



Since the t3'pe specimen is the only one known, the original descrip- 

 tion is cjuoted in full : 



Diagnosis. — A ringed form similar in coloration to L. polyzona Cope, L. triangulum 

 nelsoni Blanchard, and L. muliidncia (Yarrow). From L. polyzona it differb in the 

 complete absence of black tips on the red and whitish scales, in the completely black 

 head, and in the low number of ventral plates, 189. From nelsoni it differs princi- 

 pally in the higher number of annuli, 30, and the much narrower red rings, 2 to 3 

 scales in width. From L. multidncia it is distinguished by the low numbers of ven- 

 trals and annuli, by the fact that the black rings show scant, if any, tendency to 

 overspread the red areas dorsally, and by the mottling of the yellow rings with darker, 

 particularly on the sides. 



Range. — Patzcuaro, Michoacan, Mexico. 



Tyi'te Speciraen. — United States National Museum No. 46558 (skin and head only); 

 Patzcuaro, Michoacan, Mexico; collected by E. W. Nelson, August 2, 1892. 



Description of type specimen. — Ventrals, 189; anal single and entire; caudal scutes 

 50 plus, divided (tip of tail missing); dorsal scale rows, 21 anteriorly, 23 on middle of 

 of body, and 19 posteriorly (formula therefore 21-2.^21-19); upper labials 8 on left 

 side, 7 on right; lower labials 9; 1 preocular, 2 postoculars; temporals somewhat irreg- 

 ular, about 2+3+4, the upper left anterior temporals much reduced; loreal longer 

 than high; nasals injured on each side; anterior chin shields in' contact with each 

 other and with the first- four lower labials; posterior chin shields shorter than the 

 anterior and separated from each other by 2 or 3 small scales; other head shields normal 

 for the genus. 



Total length (tip of tail misBing), al-out 745 mm., tail length 112 mm. 



The dentition is as follows: Maxillary teeth, 14 on the left side, 15 on the right, 

 the last two distinctly enlarged; mandibular teeth, 14 on the left side 13 on the right, 

 decreasing slightly in size; palatine teeth, 13 on the left, 11 on the right; pterygoid 

 teeth, 21 on the right side. 



The color pattern is composed of 24 whitish rings on the body and 6 on the tail. 

 These rings are about IJ scales wide on the middorsal line and 2 scales wide on the 

 first row of scales; on the sides and on the belly, posteriorly, they are mottled with 

 darker. Bordering the whitish rings are black annuli about 2 scales v.ide dorsally 

 and 1 scale v.ide on the belly. The black rings are separated by red rings, 2 to 3 

 scales in width. The actual colors can not be determined from so old a specimen, 

 but there are indications that the whitish rings may have been suffused with pink. 



The head is black nearly to the tips of the parietal shields, except for flecks of whitish 

 on the lower portions of some of the upper labials. The chin is whitish except for 

 some black on the first 5 or 6 of the lower labials. The first black ring begins about 

 2 scales behind the parietals and is continuous across the tliroat. 



Remarls. — The status and significance of this form, represented as it is by only a 

 single specimen, must remain in doubt for the present. It appears, however, to be 

 more closely allied to L. muliicincia than to any other form in the genus. 



