CROCODILIANS, LIZARDS, AND SNAKES. 



531 



plates are suftused with dusky. These are only blotches. !N"o rings on 

 the tail. 



There is generally no indication of white edges to any of the scales; 

 in one or two specimens only is there an occasional and faint trace of 

 this. 



GerrJiotiotiis principis Baird and Girard. 



Catalogue 

 No 



3103 



1083 



3106 



3084 

 15194 

 15940 

 16163-8 



•!2:ini 

 22410-11 



Number 

 of speci- 

 mens. 



Locality. 



From whom received. 



Governor Campbell. 



Tolot Plains Governor Stevens. 



N. P. R. R. Survey do. 



Oregon 



Paget Sound 



Nanaimo, British Columbia : U. S. Fish Cominis.sion. 



Port Townsend, Washington do. 



Seattle, Wasliiiigton O. B. Johnson. 



Sicamous, British Columbia John Macoun. 



Vancouver I.^land. British Columbia | do. 



BARISSIA Gray. 



Bari88ia Gray, Cat. Liz. Brit. Mus., 1845, p. 54. — Cope, Proc. Aiuer. Phil. Soc, 

 XVII, 1877, p. 96. 



Identical with Gerrhonotus except in the absence of the frontonasal 

 plate. 

 The species of Barissia differ as follows : 



I. No anterior loreal plate (one pair of prefrontonasals ; dorsal scales larger than 



ventrals; no snpraaiiricular processes). 



Twenty-seven transverse series of scales, which are strongly keeled, especially 

 <)n the nape; 12-14 longitudinal rows; nasal plate touching rostral, and loreal 

 touching prefrontal; yellowish green with vertical brown bars on sides. 



B. rudicolUs Wiegmann. 



Thirty-forty transverse, 12-14 longitudinal rows of scales, all keeled, thenuchals 

 less i)rominently ; nasal plate separated from rostral, and loreal touching pre- 

 frontal; olive brown above, inoro or less light or dark spotted. 



B. imbricatus Wiegmann. 



Dorsal scales in 35 transverse and 16 longitudinal rows, eight median keeled; 

 head jdates flat ; nasal not reaching rostral ; loreal touching prefrontal ; brown, 

 with lateral vertical brown, white-edged bars B. plain/ronn Bocourt. 



Dorsal scales in 46 transverse and 16 longitudinal rows; the four median dis- 

 tinctly keeled; nasal plate separated from rostral; loreal separated from pre- 

 frontal by prefrontonasal ; tawny olive, with vertical brown, white-edged 

 bars on sides B. levicollis Stejneger. 



II. An anterior loreal plate, 2 pairs of prefrontonasals. 



a. Dorsal scales larger than ventrals. Elongate snpraauricular processes; nasal 

 separated from rostral; scales in 30 transverse and II longitudinal series, 

 obtusely keeled; greenish gray above with angular, brown cross hands; below- 

 yellow B. fimhriata Cope. 



aa. Ventral scales equal dorsals. No elongate snpraauricular processes ; nasal 

 plate sei)arated from rostral; scales in 50 transverse and 14 longitudinal rows, 

 only the median obtusely keeled; bronze green, sides with black vertical lars; 

 belly and sides with yellow spots B. antauges Cope. 



