£50.': BOTANICAL GAZETTE [AUGUS1 
nium imbedded. The homologies of the embryo sac structures of the angio- 
sperms are not yet cleared up. 
Up to 1885 there is nothing in literature to justify the assumption of such 
a gradual transition in case of the male gametophyte. Belajeff investigated 
antheridia of Selaginella and Isoetes in 1885, and the antheridia of the heter- 
osporous Filicinee in 1890. The small cell cut off from the germinating 
spore of Selaginella and Isoetes is the male gametophyte, the homologue of 
the prothallium which bears the antheridia in the homosporous Filicinee. 
The antheridium which this much reduced gametophyte bears consists of 
several peripheral cells forming a wall enclosing inner cells in which sperma- 
tozoids are formed. The peripheral cells later coalesce. In the heterosporous 
Filicinew the more complex male gametophyte shows that the transition from 
cryptogams to phanerogams is not to be sought here but rather in the hetero- 
sporous lycopods, 
In the gymnosperms Belajeff investigated only the conifers, In the Abie- 
tinez the small cells cut off from the germinating microspore represent the 
male gametophyte. The rest of the spore consists of an inner small cell sur- 
rounded by a large outer cell which develops the pollen tube. The inner cell 
divides into two, the hindmost of which disorganizes; the other again divides, 
giving rise to two cells which are the homologues of the mother cells of the 
antheridia of Selaginella and Isoetes. In the Cupressinez the male gameto- 
phyte is entirely suppressed, the pollen grain transforming itself directly into 
an antheridium, In the Taxinez the simplification is carried still further. 
In the angiosperms the conditions are the same as in the Cupressinee, 
the pollen grain dividing into two cells, the larger representing the anther- 
idium wall, which stretches into a tube, the smaller dividing into two genera- 
tive cells. 
In 1897 the studies of Ikeno and Hirase threw new light upon the rela- 
tionships of the cryptogams and phanerogams. Hirase found that the two 
generative cells in the pollen tube of Gingko develop into ciliated spermato- 
zoids, and Ikeno made the same discovery in Cycas. Webber recently made 
similar observations on Zamia, his description of the development of the 
spermatozoids corresponding with Belajeff’s description of these structures in 
Equisetum and ferns, thus adding another proof of the relationship between 
the cryptogams and cycads. Of course these observations break down the 
old division into zoidiogams and siphonogams, since Cycas, Gingko, and 
Zamia would belong to both groups.— CHAS, J. CHAMBERLAIN, 
ITEMS OF TAXONOMIC INTEREST are as follows: Recent numbers of the 
Bulletin of the Torrey Botanical Club contain descriptions of new species of 
Asclepias and a recasting of A. verticil/ata and its allies, by Anna Murray 
Vail (25 : 171-182. 1898); some new species of liverworts, with two plates, 
by Marshall A. Howe (Z. c. 183-192); descriptions of various new species 
