128 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



with the two species Garcinia Kydia and G. Treubii. "With regard 

 to the former species a great deal of doubt exists whether its flowers 

 are hermaphrodite or whether the plant is dioecious. Treub now 

 shows that G. Kydia is hermaphrodite and that fertilization takes 

 place in quite a regular manner. The archesporial cell of G. Kydia 

 becomes directly the mother-cell of the embryo sac. The four cells 

 of the tetrad arising from the division of the embryo-sac mother- 

 cell are not arranged in a single row, but usually the two uppermost 

 cells lie side by side. The lowest cell of the tetrad gives rise to 

 the embryo-sac, whilst the other three cells degenerate. The nucleus 

 of the embryo-sac divides, and the daughter nuclei take up their 

 position at the two ends of the sac. Here they divide again, but 

 the nuclei of the lower end of the sac never give rise to antipodal 

 cells. In fact, no antipodal cells are ever formed in this plant. The 

 nuclei of the upper end of the sac give rise to the normal sexual 

 apparatus in the usual way, so that we find here two synergidae and 

 the egg-cell. The two nuclei of the lower end of the sac fuse and 

 become the secondary nucleus of the embryo-sac which gives rise 

 to the endosperm by its division. Pollen tubes lying in the upper 

 part of the embryo-sac were very clearly observed, so that there is 

 every reason to believe that fertilization takes place in this plant 

 in a perfectly regnlar manner. Garcinia Treubii is dioecious, and 

 only female plants grew in Buitenzorg. In spite of this a few of 

 the flowers developed fruits and embryos. It might be concluded 

 from this that these embryos develop apogamously or parthenogene- 

 tically, but, although this appears very likely, Treub points out that 

 another explanation is not improbable. In some other dioecious 

 Garcinias Pierre has occasionally found a flower which was herm- 

 aphrodite. Although Treub could not directly observe such flowers, 

 he believes that it is not impossible that a hermaphrodite flower 

 may here and there develop in G. Treubii among the many thousands 

 of flowers produced, and thus explain the occasional appearance of 

 fertile fruits in this plant. The early history of the embryo-sac of 

 G. Treubii is similar to that of G. Kydia. — E. B. 



Eng-elmann Spruce in the Rocky Mountains, with Special 

 Reference to Growth, Volume, and Reproduction. By E. K. 



Hodsonand J. H. Foster {U.S.A. Dep. Agr. Forest Service, Circ. 170). 

 A comprehensive paper on the growth and management of Engel- 

 mann Spruce in the Bocky Mountains. 



Though the timber is less valuable than that of the Douglas Fir, 

 yet for ordinary purposes it is found useful, being close and straight- 

 grained and easily worked. There are some useful tables on the: 

 volume of growth of this spruce, and short notes on insect pests andi 

 diseases. — A. D. W. ; 



EnolOgrical Studies. By William B. Alwood {U.S.A. Dep. Agr. 

 Bur. Chem., Bull. 140; May 1911). — It has been generally stated thai 



