TlIK IJATRACIIIA OK NoKTU AMKIilCA. 



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imrcnt nuMliiiin witli tlie brilliiiiicy of.i straiifjo i'xolic, ratlier tbivu tlio 

 piillor ot iv ilweller iu the cliill.v (k'|)tlKs iiiid dark recesses of ii cavo. 

 Tlioy walk delilu'riitcly, ami swim with snmo activity, moving, as do 

 other sahunaiiders, with the limits pr«'ssed to the sides and the body 

 and tail undulating laterally. Their movements are not so active as 

 tiioso of some other species. They arc vei-y harndess and, though I 

 have handled a great niiiidter of them, have never seen them attempt 

 to bite. Their food consists of insects. 



r«r/f7/<'.v.— Occasionally a spei^imen is found which is of a uniform 

 grayish-brown. Dr. IC. K. Gait sent me snch a one front Staten Island, 

 Xew York. Two forms have been distin,i;nished by Trofessor llaird 

 which may rank as sid)species : tlie S. riihcr slirticcpH and the »S'. ruhir 

 mtnitaniis. They are described below. 



The manner in which the characters which »listinguish these sub- 

 species are found singly in variojis individuals illustrates wt^ll the con- 

 dition of a protean species. Thus of the si>ecimens with sixteen costal 

 l>lica'. refciable to S. r. monfunus, where t!ie width of the head may 

 be one-sixth the length to the j;roiu, two specimens measure thesame, 

 Oft and (t'i{ iu the same, ami another (i|, and another (.'{S4S) 7 times. In 

 one the posterior part of the par^sphenoidal patch is widened, as in the 

 Msual form. Ii; two specimens (.WTO-TO.'M) tlie sixteenth pli(!a falls over 

 the femur and does not descend before it; the vomerine series of both 

 are angulated. In Td.'ihf, from the same locality as TOM, all the char- 

 acters are those typical of S. r. ininitainis. 



In two specimens having the head and coloration of var. IJuber, from 

 Miitaw, Ala., one has lifteen plicie and angnlat«' teeth, the other sixteen 

 plica' and curved series of tet'th. In a number of >S'. r. nihcr from Ab- 

 Iteville, S. (!., one has sixteen plica-. In this variety the width of the 

 head enters the, length to gn»in usually tivv times, but varies to i}.\, r)!|, 

 and in 7(L'.{, ii\ times. 



In the typ»' of I'.JhtrissimiiN, this relation is 1 to (iA, with but lifteen 

 plica-; the truncation of the muzzle is less than described, and there 

 are no cirri. In var. Sti(!ticeps a trace <d" the same is visible. The 

 peculiar (U)arsc and sparst; spotting in this var. ami in »S'. r. moiiUinus 

 is seen in Ruber No. 7b7."5 (half giown). 



The uniform <rolor of S. r. stirtircps is nearly equaled by Xo, 7()L*;J. and 

 the white i)uni iulation of the iiits by 7b7.'> (large), though nonti are siuu- 

 lar in the puiu',tulatiou of the front ; in IStO, from Eutaw, Ala., the ab- 

 domen and gular region are sindlarly punctulate. 



As regards the size of the eyes in r.j!<ti'ist<iini(s, their longitudinal 

 diameter measures l.o the width between their anterior caiithi. These 

 sjiecimens are both small. In several small var. Ruber the measurement 

 is thesai.u', and in the smaller of the »V. r. }ftlcficcp,s ; in the larger of the 

 latter and of Ruber this measurement is as 1 : Li. NevTtheless, iu a nuni' 

 ber of var. Ruber which have just completed their metau'orpliosis the 

 proportion of front to eye is also li : 1 (Xo, oSt!)). 



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