88 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I50 



an Air Castle, 1938, p. 226). The eggs in color and size resemble 

 those of the resident form of the green heron. 



Griscom believed that the herons of this group that he described as 

 patens had the legs more brightly colored than in the other species of 

 green heron, but Van Tyne found that this was not true in the 

 specimens that he handled. 



Throughout the entire range of Butorides striafus from Colombia 

 and Venezuela south to Brazil and Paraguay occasional individuals 

 have a brownish wash, varying from a trace of pinkish buff to vina- 

 ceous-bufif, over the gray of the head and neck, sometimes also a 

 greater amount of cinnamon to clay color streaking on the lower fore- 

 neck and upper breast. A similar type of coloration is prevalent on 

 Isla Margarita ofif northeastern Venezuela where, as it is coupled 

 with average smaller size, it is recognized as a distinct subspecies, 

 Butorides striatus robinsoni Richmond. The brownish coloration in 

 birds of the striatus group, as noted, is common in Panama, west to 

 the eastern side of the Azuero Peninsula on the Pacific slope, and to 

 the lower Rio Indio (Chilar) west of the Canal Zone, on the Carib- 

 bean side. These birds, separated as Butorides striatus patens by 

 Griscom, might be considered a connecting link with the dark, rufes- 

 cent, brown-necked virescens group, since they are found with typi- 

 cal B.v. maculatus, and equally typical B.s. striatus, if birds exactly 

 like them did not appear at random through the entire South Ameri- 

 can range of striatus. While there may be occasional mixed mating 

 among those herons when they range together, this would not explain 

 the occurrence of the patens style of coloration in South America in 

 areas where the virescens type does not occur. The supposed race 

 patens is regarded therefore as individual variation in typical Bu- 

 torides s. striatus. 



CASMERODIUS ALBUS EGRETTA (Gmelin): Common Egret; Garza Blanca 



Ardea Egretta Gmelin, Syst. Nat., vol. 1, pt. 2, 1789, p. 629. (Cayemie.) 



Definitely larger than any of the other herons of white plumage, 

 with yellow bill, black legs and feet. 



Description. — Length 800 mm. to a little more than a meter. Adult, 

 pure white with long crest and dorsal plumes in nesting season. 



Measurements. — Males (5 adults, from Florida, Colombia and 

 Paraguay), wing 372-397 (386), tail 146-154 (148), culmen from 

 base 116.5-120.2 (118.2), tarsus 157-175 (166) mm. 



Females (5 adults, from Kentucky, North Carolina, Cuba, Colom- 

 bia, and Paraguay) wing 355-365 (360), tail 137-143 (140), culmen 

 from base 98.7-109.5 (104.3), tarsus 127-147 (138) mm. 



