OKLAHOMA ACADEMY OF SCIENCE 67 



parents July 24, 1922. Robins have markedly increased here of 

 late years as breeding birds. 



*Bluebird (Sialia sialis sialis). Twenty nests have been found 

 in the 3 years ; 8 of these are known to have succeeded and 2 to 

 have failed. The first broods are started in late March or early 

 April and the second broods from the middle of May till early 

 June. The earliest egg found was on March 24, 1921 ; the latest 

 brood were still in the nest on June 29, 1922. Two broods left the 

 nest when 16 days old, two when 17 and one when 18 and 19 (there 

 were 6 young in this brood). In one case the young of the first 

 brood helped feed the young of the second. 



X. IDENTIFICATION. AND ECOLOGY OF POLYPOD- 



lUM C?w) AN EPIPHYTIC FERN INCLUDED IN 



THE OKLAHOMA CRYPTOGAMIC FLORA 



M. M. WicVham 

 From t'^e Dart, of Pptholog-y, University of Oklahoma. 



Poly podium incammi (Sw.) is one of the rare, if not the only 

 epiphytic fern, recorded in the Oklahoma crytogamic flora. In 

 March, 1914, while conducting a party in field biology at Blue 

 Falls, Arm.strong, Bryan county, Oklahoma, the writer observed a 

 peculiar erowth on the hidi and arched branches of a bur-oak 

 tree {Qnercus macrocarpa) which resemb'ed a coarse and scurfy 

 moss, or lichen grov/th. Closer inspection revealed this to be a 

 perching fern. 



Among its comm.on names are : "hoary polypody," "scaly poly- 

 pody,"' "tree fern," and "resurrection fern." "Tree fern," is from 

 its habit of growing in tlie tree tops, and "resurrection," refers to 

 its habit of revival after drought. 



The growth began about ten feet from the ground, and as- 

 cended on the north side of the trunk to a height of some twenty- 

 five feet, passing out on the north sides of the major branches, as 

 well. The running rhizomes were branched and embedded in a 

 substratum of moss which found a symbiotic protection beneath 

 the fronds of the fern The fronds were thick, scurfy, and about 

 three to six inches in length. Where exposed, they were rolled 

 inward in the desiccated condition, and where shadowed the fronds 

 were practically expanded exposing a mossy green upper surface. 



Ecology 



Poly podium incanum (Sw.) "the little gray polypody," may be 

 termed a 'straggler' into our territory (Clntc) ranging from a 

 warmer region. It is most abundant in the tropics, where it grows 



