coisrTEisrTS. 



Remarks on the Blastoidea, with Descriptions of new species. 



By F. B. Meek and A. H. Worthen, of the Illinois State 



Geological Survey , — 83 



A Review of the Species of the Plethodontida and Desmogna- 



thidffi By Edward D. Gope........ 93 



Further Notes on Microscopic Grystals in some of the Gems, etc. 



By Isaac Lea 119 



Sexual Law in the Coniferse. By Thomas Meehan 121 



Descriptions of Six new Species of Fresh-water SKells. By 



Isaac Lea 124 



Notices of certain obscurely known species of American .Birds. 



(Based on specimens in the Museum of the Smithsonian 



Institution). By Robert Ridgway..... 125 



Descriptions of new Carboniferous Fossils from the Western 



States. By F. B. Meek and A. H. Worthen, of the Illinois 



State Geological Survey 137 



Proceedings of the Biological and Microscopical Department. — 



(Appendix). 



