MEXICAN SNAKES AND CROCODILIAN S — SMITH 413 



short pair of stripes five scales long; after an interval of one (two on 

 one side) scale length, follows another pair of stripes, these covering 

 seven scale lengths ; posterior to this the markings are blotchlike. In 

 the other specimens the neck stripes are unbroken for a distance equal 

 to about three or four times the length of the head. In one the poste- 

 rior third of the stripes is expanded laterally somewhat, appearing 

 blotchlike. 



The Museum has nine other Mexican specimens, from Campeche : 

 Apazote (Nos. 46399-46400). Oaxaca: Tehuantepec (No. 30260); 

 Huilotepec (No. 46473). Tabasco: Montecristo (Emiliano Zapata) 

 (No. 46522). Yucatan: Chichen Itza (No. 46570) ; "Yucatan" (No. 

 6557 [2]). Locality unknown: No. 12716, "City of Mexico," cer- 

 tainly incorrect. 



*CROTALUS LEPIDUS KLAUBERI Gloyd 



Nine 22 specimens of this race are in the Museum, as follows : Chi- 

 huahua: Lake Santa Maria (Nos. 46597-8); "Chihuahua" (Nos. 



36994,56165). Durango: Guanacevi (No. 46349). Jalisco: Bolanos 

 (No. 46472). Zacatecas: Berriozabal (No. 46454); Plateado (Nos. 



46470-1). 



•CROTALUS MOLOSSUS MOLOSSUS Baird and Girard 



Four specimens are in the Museum, from Sierra Encarnacion, 

 Coahuila (No. 46507), Dist. Guerrero, Chihuahua, 2,193 m. (No. 

 42499), Carbonero Canyon, Sierra del Carmen, Coahuila (No. 

 103738), 23 and San Esteban Island (No. 64586). 2i 



CROTALUS MOLOSSUS NIGRESCENS Gloyd 



Five specimens are from Puente Colorada, Veracruz (No. 110603), 

 and Tacicuaro, Michoacan (Nos. 110599-602). The scale counts of 

 these, in the order cited, are : Scale rows 27-25-21, 27-25-19, 27-23-19, 

 27-25-19; ventrals 171, 171, 165, 175, 166; caudals 25 ( $ ), 24 ( $ ), 

 19 ( 9 ) , 21 ( 9 , 26 ( $ ) . Nos. 110600 and 110602, which have the lowest 

 ventral counts known for nig?"escens, are somewhat lighter posteriorly 

 than the other specimens, and the black tail bands are faintly visible 

 (4 or 5 in one, 6 or 7 in the other). In the other specimens, including 

 a smaller nigrescens (No. 110601) from the same locality, the tail is 

 completely and uniformly black. The specimens in question do not, 

 however, seem to approach hasilhcus, in which the tail is considerably 

 lighter. 



33 Gloyd, 1940, pp. 109-112, map 7, pi. 11, fig. 2. 

 *> Gloyd and Smith, 1942, p. 235. 

 * Gloyd, 1940, p. 160. 



