120 



SCIENCE. 



[N. S. Vol. VII. No. 161. 



whicli lie had been able, by growing male 

 and neuter plants of this species in rich soil, 

 to change them to female plants, and by 

 removing a part of the stored food supply 

 of female plants to change them to male. 



14. On Polyemhryony and its Morphology in 

 Opuntia vulgaris, Hill. Dr. W. F. Ga- 

 NONG, Smith College. 



The author has found this species to be 

 polyembryonic, with a double morpholog- 

 ical basis ; one set of embrj'os develops from 

 a mass of tissue which he believes to arise 

 from the fertilized egg-cell, while the other 

 arises on the walls of the embryo- sac, but 

 not from the nucellus, but probably from an 

 endosperm cell, which, if true, is a new 

 mode. 



15. Contributions to the Morphology and Biology 

 of the Cactacece. Part II., Tlie Comparative 

 Morphology of the Embryos and Seedlings. 

 De.W. F. Ganong, Smith College. 

 This paper is a continuation of the au- 

 thor's earlier studies on this family. It de- 

 scribes and figures germinated embryos of 

 most of the genera and many important 

 species, discusses germination and growth of 

 the seedlings and the unfolding of the pecu- 

 liar morphological features of the adults, 

 together with the form, size and color fac- 

 tors of the embryos and seedlings, and what 

 these show of importance for the determi- 

 nation of the phylogeny of the genera. 



16. Hie Morphological Significance of the Lodi- 

 cules of Grasses. Dr. W. W. Rowlee, 

 Cornell University. 



A STUDY of the flowers of Bamboos 

 leads to the conclusion that the lodicules of 

 grasses represent a reduced perianth. The 

 three lodicules in Arundinaria alternate 

 with the stamens, and may, therefore, be 

 considered the inner whorl or petals. The 

 stamens are directly opposite the midribs of 

 the carpels, and indicate that the inner 

 whorl of stamens, present in some bam- 

 boos, is suppressed in Arundinaria. Hackel 



interpreted the lodicules as distichous 

 bracts. 



17. Observations on the American Squaw-root 

 (Conopholis Americana, Wallr.). Dr. Lucy 

 L. W. Wilson, Philadelphia. 



This paper contained an exhaustive study 

 of the vegetative characteristics of this par- 

 asite and of its relations to its invariable 

 host, the Oak. Because of its extreme deg- 

 radation and the intimacy of its relation 

 with the host, the author compared it with 

 members of the Balanophorese and Eafflesi- 

 acese rather than with parasitic Scropulari- 

 acese. 



18. Water Storage and Conduction in Seneeio 

 prcecox, DC, from Mexico. Dr. John W. 

 Harshberger, University of Pennsyl- 

 vania. 



This species, inhabiting volcanic beds in 

 the Valley of Mexico, shows a remarkable 

 method of storing water in the pith, and 

 prevents its too rapid loss in the dry season 

 by protective layers of cork and balsam. 

 The water is conducted to the vegetative 

 points by bundles which project into the 

 pith. The histological characters are fully 

 described. 



19. Notes on the Embryology of Potamogeton ., 

 Mr. K. M. Wiegand, Cornell University. 

 The author had studied the origin and 



development of the embryo-sac, fertilization 

 and development of the embryo in this 

 species. Although the normal number of 

 cells is present in the egg-apparatus and 

 the antipodals they form irregularly. Of 

 particular interest is the fact that the de- 

 finitive nucleus cuts off a very large basal 

 nucleus, as in Sagittaria, before endosperm 

 formation proceeds. 



20. Recent Experiments and Observations on 

 Fruit- Production in Amphicarpcea. Dr. Ade- 

 line Schively, Philadelphia Normal 

 School. 



This paper continues the author's recently 

 published observations on this subject, and 



