438 BOTANICAL GAZETTE [DECEMBER 
strong tendency to tuber formation which finally overcomes all obstacles is 
due, the author thinks, not only to the internal force which looks to the propa- 
gation of the species, but also to a demand for organic symmetry ; the occa- 
sional development of potato tubers without starch, and therefore functionally 
impotent, appears to favor this conclusion. 
The author has thus been enabled to establish upon a firmer basis than 
ever before his ideas as to the great plasticity of plants and the vicarious 
nature of their organs. Perhaps the most astounding thing of all is the 
power shown by a mature organ, like the tuber of Oxalis or Dahlia, to be born 
again, as it were, and start on a period of. secondary growth. The plasticity 
of a young organ is well known, and perhaps not so surprising, but one would 
scarcely have expected to see such evidences of life and vigor in a specialized 
organ like a tuber— HENRY C. COWLES. 
THE ORIGIN of the cilia of the spermatozoid is very briefly but clearly 
traced by Belajeff5 in Gymnogramme sulphurea and Eguisetum arvense. In 
Gymnogramme two centrosomes (the blepharoplasts of Webber and others) 
make their appearance at opposite poles of the nucleus of the grandmother 
cell of the spermatozoid. The division of this nucleus is not accompanied 
by a division of the centrosome, and consequently each of the resulting cells 
receives only a single centrosome. The centrosome, originally spherical, elon- 
gates into a narrow band lying alongside the nucleus, and the cilia arise from 
the peripheral portion of the band. 
The sequence is the same in Equisetum, but here the writer was able to 
show that the band is made up of a row of intensely staining granules and a 
less deeply staining portion. Each granule gives rise to a single cilium. 
he spherical organs which give rise to the band are regarded as genuine 
centrosomes, and Belajeff would homologize with them the blepharoplasts of 
Webber (Zamia) and Shaw (Marsilea and Onoclea), and also with the cilia- 
forming centrosomes of Hirase (Gingko) and Ikeno (Cycas). He would also 
homologize the cilia-forming band with the “middle piece” of the animal 
spermatozoon, as described by Hermann for the salamander. — CHARLES J. 
CHAMBERLAIN, 
IN A sTuDy of the influence of weather and the condition of the soil upon 
the anatomical structure of plants, W. Meyer® objects to culture experiments 
and goes for his material to nature, where plants may be found under the 
same conditions for many generations. He compares numerous members of 
the Caryophyllacez, chiefly alpine forms, and shows how species in different 
divisions of the same family have a close resemblance to one another when 
growing in similar situations. For example, species of the Silenez, Alsine, 
5 Ueber die Cilienbildner in den spermatogenen Zellen. Ber. d. deutsch. bot. 
Gesell 16:140-144. A/. 7. 1898 
° Bot. Centralb. 79: 337-350. 1899. 
