24 THE UNIVERSITY OF OKLAHOMA 



(Icnus: Spongilla 



Family 5 : Spongillidae 



Species: Fragilis, Leidy, 1S51. 

 Tlie question is with reference to the species ; as to whether 

 or not this is "fragilis." 



Characters. "Sponge encrusting in sub-circular patches, thin 

 at edges, occasionally one or more inches thick at the middle. In 

 most varied situations, apparently preferring standing water, though 

 also in runn'.ng water. Alnmdant. Gemmules abundant; primarily 

 in one or more pavement layers. Also in compact groups surrounded 

 by a cellular parenchyma, charged with sub-cylindrical spined acer- 

 ates. Skeleton spicules smooth, slightly curved, rather abruptly 

 pointed. True dermals wanting. Found in m.ost of United States." 

 — (Ward & Whipple.) 



Ecology of Shuler's Lake. 



Shuler's Lake is an impound of water fed by springs, which 

 has been undrained for over twenty years. It is situated in the 

 north part of the city of Durant, Bryan County, Oklahoma, where 

 it v.-as established by Dr. Early, in territorial days, soon there- 

 after passing into the hands of Dr. J. L. Shuler, who maintained a 

 sanitorium near its miargin in a grove. The body of water fills 

 a deep ravine, grading from a shelving shore at one end to a 

 depth of fifteen to twenty feet at the other. Deep dark, and oozy 

 at its north end, it shelves to muck and leaf-strewn reaches at the 

 south, giving every gradation in pond life, as well as zonation. In 

 the center is a small island, and near this are submerged timbers 

 of a diving tower. Sunken piles are also to ])e m.et with below 

 the surface of the water. It is in such conditions as this, with 

 clear, non-turbulent water, cool depths, and submerged timbers, that 

 tlie first sponges reported in Oklahoma waters were found, in a 

 \ery typical optimum environment. During the past two decades 

 of its existence, visited by migratory birds and mammals Shuler's 

 Lake lias become the collecting ground and conservatory of a 

 rich and extensive pond fauna and flora. 



Biblography. 



Ward, Henry Baldwin, and Whipple, George Chandler, 1918, 

 Fre.-h Water Biology. 



Parker, T. Jeffery, and Haswell, Wm. A., 1910, A Text Book 

 of Zoolojjy. Vol. I. 



Cambridge Natural Hi'^tory. 1906, Porifera, Igerna B. J. Sollas. 



