39. NATRIX 785 
Tropidonotus leberis validus GARMAN, Mem. Mus. Compr. Zool. Cambr., 
Vol. VIII, No. 3, pp. 28, 143. 
Regina valida celeno Cops, Bull. U. S. Nat. Mus., No. 32, 1887, p. 74. 
Natrix valida valida Core, Proc. U. S. Nat. Mus., Vol. XIV, 1892, p. 670; 
Cops, Report U. S. Nat. Mus. for 1898, 1900, p. 984, figs. 258, 259. 
Natrix valida celeno Corr, Proc. U.S. Nat. Mus., Vol. XIV, 1892, p. 670; 
Core, Report U. S. Nat. Mus. for 1898, 1900, p. 986, fig. 260. 
Tropidonotus validus BoULENGER, Cat. Snakes Brit. Mus., Vol. 1, 1893, 
p- 237; Ginruer, Biologia Cent.-Amer., 1894, p. 134; Mocquarp, 
Nouv. Arch. Mus. Hist. Nat., ge Ser.,Vol. I, 1899, p. 329; Dirmars 
Reptile Book, 1907, p. 245. 
Natrix valida Van Densurcu, Proc. Cal. Acad. Sci., Ser. 2, Vol. V, 
1895, p. 152; Van Densurcu, Proc. Acad. Nat. Sci. Phila., 1897, 
p- 464; STEJNEGER & Barpour, Check List N. Amer. Amph. Rept., 
1917, p. 97; VAN DensurcH & Sievin, Proc. Cal. Acad. Sci., Ser. 
4, Vol. XI, 1921, pp. 52, 68; Netson, Mem. Nat. Acad. Sci., Vol. 
XVI, 1921, pp. 114. 115. 
Natrix celaeno Van DenBurGH, Proc. Cal. Acad. Sci., Ser. 2, Vol. V, 
1895, p. 154. 
Description.—Head distinct from neck, flat-topped, with 
rather narrow, rounded snout, and temporal regions some- 
times swollen. Rostral large, bounded behind by internasal, 
anterior nasal, and first labial plates. Plates on top of head 
are a pair of internasals, a pair of prefrontals, a long frontal, 
supraocular of each side, and a pair of large parietals. An- 
terior and posterior nasals distinct. One loreal. Preoculars 
one or two, or very rarely three. Postoculars usually three, 
sometimes two. Temporals normally one followed by two, 
sometimes 1+3. Supralabials eight, or very rarely seven, 
fourth and fifth reaching eye, sixth and seventh largest. 
Infralabials usually ten, sixth largest, first pair meeting on 
median line. Genials in two pairs, posterior longer than 
anterior. Scales on body in 19 rows, all keeled except occa- 
sionally in outer row. Anal plate divided. Gastrosteges 
varying in number from 139 to 154. Urosteges in two 
series of from 65 to 83. 
