vi Contents. 



Papers Published — Continued. page 



9. Wm. H. Roever. — Geometrical constructions of the lines 

 of force proceeding from (a) two parallel electrified 

 lines, (6) two electrified points. — Issued June 30, 

 1896 201 



10. J. B. S. Norton. — A study of the Kansas Ustilagineae, 



especiall}' with regard to their germination. — Plates 

 XXV.-XXIX.— Issued November 9, 1896 229 



11. Milton Updegraff. — Flexure of telescopes. — Issued 



November 21, 1896 243 



12. Wm. H. Roever. — Geometrical properties of the lines of 



force proceeding from (a) a system consisting of an 

 electrified plane and an electrifled line parallel to the 

 plane, (6) a system consisting of an electrified plane 

 and an electrified point.* — Issued January 19, 1897... 273 



13. Henry S. Pritchett. — Results of double star observa- 



tions made with the equatorial of the Morrison Obser- 

 vatory.— Issued April 22, 1897 299 



14. Charles Robertson. — North American bees. — Descrip- 



tions and synonyms. — Issued May 7, 1897 315 



15. Charles R. Ketes. — Relations of tlie Devonian and Car- 



boniferous in the upper Mississippi valley. — Issued 

 Junel, 1897 357 



16. Frank Collins Baker. — Critical notes on the Muri- 



cidae. — Issued June 12,1897 371 



17. Robert Combs. — Plants collected in the district of Cien- 



fuegos. Province of Santa Clara, Cuba, in 1895-1896. — 

 Map, and Plates XXX.-XXXIX.— Issued September 



13, 1897 393 



18 William Trelease. — An unusual phyto-bezoar. — Plate 



XL.— Issued November 30, 1897 493 



19. Julius Hurter. — A contribution to the herpetology of 



Missouri. — Issued December 31, 1897 499 



20. Title-Page, prefatory matter and index of Vol. VII. 



Record from July 1, 1894 to Dec. 31, 1897.— Issued 



February 21, 1898. 



List of Authors .' , 505 



General Index 506 



Index to Genera 510 



♦ See note by author, on p. ill. 



