76 BULLETIN 114, UNITED STATES NATIONAL MUSEUM. 



by two small scales; loreal usually longer than high, less often about 

 as high as long; scale rows on middle of body, 23 or 25, formula 

 usually 23-21-19, or 21-23-21-19, often 23-25-23-21-19. 



This is a somewhat smaller and slenderer form than the eastern 

 representatives of the group. In proportions it is close to splendida. 

 The tail varies from 0.107 to 0.145 of the total length (average for 

 males, .130, for females, .120). The largest specimen examined was 

 from Tehama County, California, and measured 1,280 mm.; the next 

 largest was 1,234 mm., from ' 'California." 



The pattern is of white rings, 28 to 49, often disposed more or less 

 obliquely, and separated by a ground color of black or dark brown; the 

 rings widen rather suddenly on the sides, from one to two scales 

 on the middorsal line to three to six on the first row of scales, and 

 cross the abdomen as broad bands. In distinction from yumensis 

 and conjuncta, the scales of the white rings are white to their bases. 

 However, the basal shading, characteristic of these forms, may 

 appear at almost any point in its range, and for identification in 

 such cases study should be made of the pattern and scalation of the 

 head (see Table of Comparisons, p. 77). The markings on the head 

 are typically like those of yumensis, but further white spotting may 

 be developed, particularly along the coast, and examples are not 

 infrequent in which there is more white on the head than in conjunda. 



The copulatory organ may be described as follows: Bilobed; 

 sulcus single, extending over one of the lobes, and ending in a small 

 bare space; calyces strictly apical, fringes few, distinct or very short, 

 passing into spines; latter close set, somewhat larger toward the 

 base, covering from a third to less than half of the distal end of the 

 organ, suddenly replaced by a few minute spines which soon dis- 

 appear altogether, or which may not be present at all. A specimen 

 from Washington County, Utah, shows a few pits as traces of the 

 minute spines, but these are not evident at all in one from Overton, 

 Nevada. Another from southern Nevada has the large spines pass- 

 ing rapidly, but not abruptly, into minute spines, and the latter 

 then soon disappearing. Specimens from Palo Alto show minute 

 spines only very close to the large ones. 



The dentition of hoylii is as follows: Maxillaries 13 or 14, subequal 

 except the last two or three which are slightly stouter; mandibulars, 

 14 or 15, longer in front, diminishing in size posteriorly; palatines, 

 8 to 10, usually 9, subequal, a little larger than the pterygoids; latter 

 13 to 17, diminishing posteriorly. 



Although there is usually no difficulty in correctly identifying 

 specimens of hoylii, yumensis, and conjuncta, nevertheless puzzling 

 individuals will be found. Adult examples of yumensis and conjuncta 

 need never be confused, but specimens of hoylii can be foimd to 

 bridge all the distinctions. If the locality of a specimen is unknown, 



