56 



BULLETIN" 15 4, UNITED STATES NATIONAL MUSEUM 



The preservation of the primitive types, miirinus and aruhensis, 

 on islands, instead of on tlie mainland, is not without precedent. 

 It may be explained by the theory that the ancestral viurinus stock 

 was once a mainland type, but that with topographical changes in 

 the region north of Venezuela, this stock Mas isolated on the islands, 

 Bonaire, Curasao, and Aruba, while on the mainland is was changed 

 to the progressive ancestral lemniscatus stock. Since Bonaire is 

 farthest from the mainland, it was probably isolated first, and it is 

 not surprising that the presumably least specialized modern group 

 of individuals is to be found here. Before the isolation of Curacao 

 and Aruba, the ancestral murinus stock apparently became modified 



n\scatua 



oteUifer 



CoTrvraon stock of 

 nigr^co\or an8 1 emtw s c a\"us 



Ancestral 



leff>T^\5catu5 



stock 



Ancestral mur\rvus stock 

 Tnod\t\e^ toward 

 lemniscatus 



Tn\ir\nus 

 n Curacao) 



mur\T\u5 



(On b 



. _oriaArel 

 Ancestral 

 •murvnus 

 stock 



Figure 12. — Diagkam of the supposed eelatioxships wrrniN the lemniscatus 



GROUP 



toward lemnUcatus and this, if true, will account for the present 

 transitional nature of these particular insular populations. 



The writer's interpretations of the genetic relationships within 

 the lemniscatus group are expressed by the foregoing diagram. 



THE DEPPII GROUP 



CNEMIDOPHORUS DEPPII DEPPII (Wiegmann) 



MANY-LINED RACE-RUNNER 



1834. CUicmidophorKs- dcpijii Wiegmann, Herpetologia Mexieaniia, p. 29, (type 

 locality, " Mexico ").— Gray, Cat. Liz. British Mus., 1845, p. 22.— Bocourt, 

 Miss. Sci. Mex. et Amer. Cent., vol. 3, 1874, p. 281, pi. 20c, figs. 5, 5a-d; pi. 

 20d, figs. 1, la-&.— O'Shauohnessy, Zool. Bee. for 1878, vol. 15, 1880, 

 " Beptilia ", p. 7. — Sumichrast, La Naturaleza, ser. 1, vol. 6, 1884, p. 39. — 

 Garman, Bull. Essex Inst,, vol. 16, 1884, p. 13.— Boxtlenger Cat. Liz. 



