Poisonous Snakes of the World 



'2. Tiiil niiiy Ihi uImhiI Imlf diirk dt riiif^t-il. II' 

 riii;;»Ml, llio ll^jlit color is lliiit of tlio liody; 



•">. I'liltiTM nsiiiilly of ('rossl)!iiiils or spots ral licf 

 iliiiii (liitiiioiuls; 



4. I'suiilly 4 scnies iK'twi-cii nasals ainl in con 

 tact Willi rostral. 



Prairie Rattlesnake, ( rofn/its v. v'uidis (Kadncs- 

 t|iif). 



KuuiRE 17. I'l-Mii'ii' KmI llcsiKiUc. Ciiildliis V. riridi.f. 

 l'huti> l.y I,. .M. Khml.cr. (Set- also jilalf III. tif?. 3.) 



Ideiilificatinii : I-if;lit diagonal si ripe bcliiiul eye nar- 

 row ; Imdy lilolclies rectangular, usually with narrow 

 lisht eilges : fiiinincl eolor often greenish-gray or olive- 

 lirown. 



Average length 3 to 4 feet; niaxiniuni a little under 

 ."> feet : males larger than females. 



Distribiitinti : South Dakota, Xeliraska. and Kansas 

 west to about the Continental Divide; north into .south- 

 ern Canada, .south into extreme northern Mexico. Oc- 

 curs in dry grassland and rocky hills: on open rocky 

 mountain slopes to at least 0,000 feet. 



Great Basin Rattlesnake, C r<if((hts r. hiloxus Klatl- 



IhT. 



Iili iili/lrdtiiiii : l.lglil stripe heliind eyes wider; pal- 

 lern of croHsbunds usually wilhout Hgbl cilgeH : ginund 

 color bulT rir drab yellow. 



.\venige lenglh 'Jl l<> 3.'i Inches; nja\ljiinjji .'>() iricheH. 



Ili.iliiliiitiiiii : Weslcrn llah, soulhcra Idaho, Nevada, 

 soulbcaslein (ircgon. ['"reipienls arid (o seminrld rocky 

 area.M. 



Pacific Rattlesnake, ('rohiliix r. (ircf/dims TTol- 

 lirodlc. 



Iiliiiti/icdtiiin: I.igbl stripe behind eye wide, often 

 indistiiHi; |iatlcrn of dianxinds or hexagonal blotches; 

 ground inliir dark gray, olive (Pi' brown, ('riitfiliin r, 

 li<llrri. a southern subspecies, differs from iir(!/iiiiiin only 

 ia minor iletails. 



Average length ;'. to I feet; m;i\iniiiiii a lilllc over fi 

 feet. 



DistriliiiliDii : Soutbci-ii Hrjtish Coliinibia, western 

 Washington, most of Oregon and the northern two- 

 thirds of California, southern California niostl.v west of 



CL': 









PiGUKE 10. — Southern Pacific Rattlesnake, Crotalii.s viri- 

 (lis htlhri. Photo by Findlay E. Russell. 



S^ 



FiGUKE 18. — Great ISasin Rattlesmike. Cruldhia riridin 

 liitosus. Photo by New York Zoological Society. 



the coast range, the northern half of Baja California. 

 (Composite range for v. uniiin^iix and r. lullcfi ) . Ab- 

 sent from the humid Pacitic Northwest and largely 

 confined to seniiarid regions in Washington and Oregon. 

 Common over much of California from sea level to 

 11,000 feet but avoids extreme desert conditions. May 

 be plentiful in agricultural districts and suburbs. 



Roiiarks : Rattlesnakes of the CrotaUis viriiUx group 

 are largely diurnal, although they avoid intense light 

 and heat. In the northern part of their range they 

 assemble in great numbers to hibernate. 



In disposition these snakes are. on the average, less 

 irritable than diamondbacks and less likely to make a 

 determined defense. A characteristic defensive gesture 

 is to protrude the tongue as far as possible and wave 

 it slowly up aiul down. 



Bites from rattlesnakes of the riridis group are rela- 

 tively common. There is evidence that venom of the 

 Pacific subspecies orcganus and hrJJvri is more toxic 

 than that of eastern subspecies. Numbness and prick- 



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