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VI 



CONTENTS 



[volume xliv 



Fertilization and embryogeny in Ephedra trijurca. 



Contributions from the Hull Botanical- Labora- a- - 



tory. CII (with plates XX-XXII) - -' -■' W.J.G.Land 273 

 The development of the seed in Poritederiaceae (with 



plate XXIII) -.-..-.. IF. C. Coker 293 



The forest formations of Boulder County, Colorado ^ 



(with tu'-elve figures) - - " - " - ' - " - " Robert T. Young 321 

 Fertilization in Cypripedium. Contributions from the 



Hull Botanical Laboratory. CHI (with plates 



XXIV-XXVII) - . ■ - - - ■ Lula Pace 353 



Germination of seeds of water plants. Contributions 



from the Hull Botanical Laboratory, CIV - William Crocker 375 



On twan hybrids - _...-- Hugo de Vries 401 



A contribution toward the knowledge of the genus 



Washingtonia (with twelve figures) - - - 5. B, Parish 408 



Araucariopitys, a new genus of Araucarians (with 

 ■ plates XXVni-XXX) ' - - " - . - - Edward C, Jeffrey 435 



Differentiation of sporocarps in Azolla. Contribu- 

 tions from the Hull Botanical Laboratory. CV 

 (with plates XXXI and XXXII) - - - Wanda M. Pfeiffer 445 



Briefer Articles — 



The black-fruited Crataegus of western North 



America - - C. S, Sargent 64 



Names of North American trees - - - C 5. Sargent 225 

 A remarkable case of polyspermy in fems (with 



one figure) ------ William L, Woodburn 227 



Some new Washington plants - - - - H, H, Bartlett 302 



Some perplexities of the indexer - - - Mary A, Day 304 



Notes on two California Nemophilas - - - Harley P. Chandler 381 

 An unusual method of vegetative reproduction in ' 



Dionaea muscipula (with one figure) - John IF. Harshberger 382 

 Branching sporangiophores of Rhizopus (with one 



figure) - - - - - - - ■ - LeRoy H. Harvey 382 



+ 



Current Literature ^ 67, 147, 228, 307, 384, 455 



For titles of books reviewed see index under 

 author's name and Re\aews. 



Papers noticed in "Notes for Students" are in- 

 dexed under author's name and subjects. 



News - - - - - - - - - 79, 160, 240, 320, 400, 464 



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DATES OF PUBLICATION 



No. I, July 20; No. 2, August 16; No. 3, September 18; No, 4, October 19; 

 No. 5j November 16; No. 6, December 18. 



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