Specimens examined (7).—Central National Forest, near Pup´yong-ni, 2 (KU), 1 (UMMZ); 4½ mi. W Chip´o-ri, 1 (KU); 5 mi. N P´yong-taek, 1 (KU); 5 mi. E Seoul, 1 (KU); 5 mi. ESE Seoul, 1 (KU).
Remarks.—Individuals were observed or taken on dry, scrubby hillsides and in grassy upland areas. One of the three snakes from the Central National Forest was captured on a steep, forested hillside among granite outcroppings; another was obtained there along a stream bank and had eaten three bats, Murina aurata (see Jones, 1960:265), and one mouse, Apodemus sp. (tail only found). P. M. Youngman reported (personal communication) finding a rat (Rattus sp.) in the stomach of one individual. A female (KU 38830, length
of body, 1180) that was obtained on June 2 contained 17 eggs, each approximately 32 mm. long. The ventrals of two females numbered 223 and 229, and the subcaudals of the latter 70. Ventrals and subcaudals of five males were, respectively, 211, 213, 214, 215, 216, and 71, 75, 75, 69, 75.
The coloration and pattern of our seven specimens are of interest in view of the probable intergradation between E. s. anomala and E. s. schrencki in northern Korea (see comments by Shannon, 1956:46). The smallest specimen (KU 38831), having a total length of 335 (280 + 55), was obtained 4 mi. N P´yong-taek on September 24. It is nearly uniform pale brown (lacks a dorsal pattern) and additionally is characterized as follows: incomplete pattern on the head; no black postocular band (pale brown with black posterior border); ventrolateral extensions of the head pattern that form longitudinal stripes of white on the third row of scales; a pale whitish stripe on the sixth and seventh scale rows that extends posteriorly to the level of the fortieth ventral and that has a narrow black border (sometimes interrupted); small and indistinct blackish markings and pale stripes on sides (no higher than sixth row of scales); underside of the head whitish; and venter grayish, having blackish margins on the ends of ventrals posteriorly. KU 38831 is unusual and perhaps anomalous in having a pattern that does not conform to the juvenile pattern of either subspecies.
A female (KU 38830), having a total length of 1390 (1180 + 210), from 5 mi. ESE Seoul conforms to descriptions of anomala in being uniformly pale brown above and in having indistinct dark smudges on the sides; the ventral surface is whitish having indistinct dark smudges, brown spots at the ends of each ventral, and the posterior edge of each ventral brown. A male (KU 40125), measuring 1090 (890 + 200) in total length, from 5 mi. E Seoul, is pale brown above and lacks markings on the anterior part of the body. Indistinct dark markings occur at midbody, whereas the posterior quarter of the body and tail have well-defined black bands on a buff background. The black bands posteriorly are arranged in pairs; each pair of bands is separated by two and a half to three scales, whereas the bands of each pair are separated by only one and a half scales. The ventral surface has an obscure marbled pattern. Our largest specimen, a male (UMMZ 113454) having a total length of 1488 (1230 + 258), from the Central National Forest, resembles KU 40125, except that pale brown blotches (29 on body, one blackish on neck) and dark lateral spots occur anteriorly on the body.
Another female (KU 38860, body length, 970) from 4½ mi. W Chip´o-ri, our northernmost locality of record, has a fairly distinct pattern dorsally. The 30 dark brown, black-edged blotches that are separated by a buff background are not arranged in pairs (as in KU 40125); the dorsal blotches sometimes alternate with small lateral blotches. The ventral surface is marbled throughout.
Two males from the Central National Forest, having total lengths of 1105 (920 + 185) and 830 (690 + 140), generally resemble one another in having the head and neck dark brown or blackish and the anterior part of body dark brown, but discernibly blotched. The posterior part of the body and tail of each bears well-defined blotches (dark brown or black) with buffy interspaces; the dorsal blotches are sometimes arranged in pairs. The ventral surface of each is marbled throughout. These two males are noteworthy in that the pattern anteriorly is obscure, but the ground color is dark, not pale as in the two specimens from the vicinity of Seoul.
Agkistrodon halys brevicaudus Stejneger
Agkistrodon blomhoffii brevicaudus Stejneger, Bull. U. S. Nat. Mus., 58:463, July 22, 1907 (type locality, Pusan, Korea).