VI 



Contents. 



Papers Published — Continued. PAGE 



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

 of foroe proceeding from (a) two parallel electrified 

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

 1896 201 



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



especially 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 electrified 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 the 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. iii. 



