400 Journal of Applied Microscopy. 



epitheliuin as being more appropriate. She sees in this layer a digestive layer, 

 as did Guignard, rather than a layer for the protection of the sac, as Hegelmaier 

 suggested. 



The antipodal cells are found to vary in number, form, and the number of 

 nuclei which they contain. They are believed to be partly digestive and partly 

 conductive in function. Their densely staining protoplasm, and their tendency 

 in some species to enlarge and burrow back into the chalazal region (we see no 

 reason for adopting the term pseudo-chalaza) are cited in support of this view. 



It will not be calling in question the soundness of the author's conclusions if 

 it be suggested that the view of many botanists, following Strasburger, that the 

 antipodals are, morphologically, a prothallial region, need not be set aside upon 

 the discovery that they have acquired a special physiological function. Certainly, 

 no one would claim that the so-called -epithelial layer ceases to be a part of the 

 epidermis becavise it has, in many cases, become glandular 



A strong point in the author's favor is found in the sharp differentiation of 

 the cells of practically all the ovules studied, into an outer region of flattened 

 cells, presumably to protect the growing embryo, and an inner, fan-shaped region, 

 whose cells, elongated radially, all converge toward the sac. That this region 

 serves to conduct nutritive materials to the sac, is hardly to be doubted. As the 

 embryo grows, the " digestion " of the cells of the ovule begins in this region, 

 along the sides of the sac, while a strand of elongated cells is left behind the sac, 

 forming almost a direct path from the end of the vascular bundle to the antipodal 

 cells. This last fact, by the way, while it argues in favor of the conductive func- 

 tion of the antipodals, argues just as strongly against any digestive activity on 

 their part. 



It is unfortunate that the figures which accompany this important paper are 

 unsatisfactory. The text figures are too small to show cell details, and the plates 

 represent the sacs and epithelial cells somewhat diagrammatically, and show but 

 a few of the surrounding cells. A few ovules, carefully drawn with their embryo- 

 sacs, would have made a valuable addition to the paper. 



W. D. Merrell. 

 Chicago. 



CURRENT LITERATURE. 



Benecke, W. Mechanismus und Biologie des Palla, E. Ueber die Gattung Phyllactinia. 



Zerfalles der conjugatenfaden in die einzel- Bar. d. dentsch. bot. Gesell. 17: 64-72, 



nen zellen. Jahrb. f. wiss. Bot. 32 : 453-476, 1899. 



'^99- Scott, D. H. On the Structure and Affinities of 



Campbell, D. H. Notes on the Structure of the Fossil Plants from the Paleozoic Rocks. 



Embryo-sac in Sparganium and Lysichiton. II. On Spencerites, a New Genus of Lycopod- 



Bot. Gaz. 27 : 153-166 PI. 27, 1899. iaceous Cones from the Coal Measures, 



Chamberlain, C. J. Oogenesis in Pinus laricio. Founded upon the Lepidodendron Spenceri 



Bot. Gaz. 27: 268-279. PI. 4-6, 1899. of Williamson. Phil. Trans. Roy Soc. of 



H«..ik»..4 ru iju 1 ' ■ 1 TTi ' T5 Lond. Ser. B. 189: 8vio6. PI.12-1 q, iSqS. 



noulbert, tn. Phylogenie des Ulmacees. Rev. -^ O' v 



gen. d. Botanique. 11: 106-119. PI. 2-3, Tyler, A. A. The Nature and Origin of Stipules. 



1899. Ann. N. Y. Acad. Sci. 10: 1-49, 1898. 



Nawaschin, S. Resultate einer Revision der ^ard, H. M. On the Biology of Stereum hir- 

 Befruchtungsvorgange bei Lilium martagon suium. Phil. Trans. Roy. Soc. of Lond. 



und Fritillaria tenella. Bull, de I'Acad. Ser. B. 189: 123-134. PI. 17-21, 189S. 



Imp. des Sci. de St. Petersbourg. 9: No. 4, 

 1898. Rev., Bot. Centrlbl. 78: 241-245, 

 1899. 



