370 Journal of Applied Microscopy. 



of the polar nuclei. This union is generally with the upper polar, but if the 

 lower one happens to be more conveniently situated, the male nucleus will be 

 attracted to it. Hence the phemomenon cannot be explained by the fact that 

 the two equivalent male nuclei are attracted respectively by the oosphere nucleus 

 and its sister, the upper polar. In either case the ultimate fusion of all three 

 nuclei is recorded. 



\ A case figured, in which the male nucleus, coiled like a closely compressed 

 letter S, lies in the angle between the fusing polars, is cited as presenting a 

 condition which, with the less perfect technique of eight years ago, might have 

 been taken for a pair of fusing centrosomes. The male nucleus in question is figured 

 as lying upon the polars, whereas the most favorable position for finding centro- 

 somes is more to one side. And it will be difficult for many persons to see how 

 such an S-shaped body could be cut so as to show the fwo pairs of fusing 

 centers on opposite sides of the polar nuclei, as they have been figured in the 

 familiar quadrille. 



The fusion nucleus, whether of oospore, or endosperm, preserves the 

 external marks of its dual or triple nature even into prophase stages. Under 

 such conditions as have been described, the increased number of chromosomes 

 in endosperm nuclei may find an easy explanation. 



The male nuclei are described as long and variously twisted bodies, many 

 of them presenting forms which, as noted by Nawaschin, suggest a possible 

 motility. While they are devoid of cilia and cytoplasm, they nevertheless are 

 entitled to the name of antherozoids. 



It may be well to call attention to somewhat similar observations made by 

 other botanists. Golinski- reports male cells in pollen grains and tubes of 

 Triticum and other grasses, which resemble the " antherozoides of a fern or of 

 Charay His figures are, unfortunately very unsatisfactory. Mottier-^ figures 

 a coiled male nucleus closely applied to the female, in LUiuvi martagon (see his 

 figure '25). Indications Of a male nucleus uniting with the polars have been 

 found vci Lilhun philadelphicnm by students at Chicago during this last year. 

 The. reviewer has found elongated, and often spirally twisted male cells in the 

 pollen of Silphinm, the figures for which are soon to be published. It would 

 seem, then, that such reminiscent forms of male cells are to be looked for almost 

 anywhere, since they have been found in such widely separated groups as the 

 Gramineffi and Liliacea and the Compositae. 



W. D. Merrell, Chicago. 



Boirivaut, A. Recherches sur les Organs de ^j^e general facts of correlation have 

 Remplacement chez le Plantes. Ann. d. ° 



Sci. Nat. Bot. Ser. 8, 6: 309-400. pi. 17-21. been observed and studied for a long 



'^98- time, indeed, many common horticul- 



tural practices are based on some knowledge of them. M. A. Boirivaut has 

 recently studied the subject from a new standpoint. He sets out by asking him- 

 self the following questions : 



Within what limits can new organs replace old ones ? 



(2) Bot. Cent. 55: 1-17,65-72,129-135, 1893. 



(3) Jahrb. f. wiss. Bot. 31 : 125-158, 1898. 



