1897] NOTES AND COMMENTS 85 
two of them should be thus thrust upwards into the water, and kept 
upright there, was a mystery. It seemed probable to us that it was 
done to secure respiration. The sand of the shoal was literally 
packed with these animals, and there must have been hundreds of 
thousands or, perhaps, millions in the whole shallow.” The species 
was near or in the genus Ophiopsila. The account is extracted from 
the miscellaneous notes in the first number of Annotationes Zoologicae 
Japonenses. 
A BOTANICAL DISCOVERY FROM JAPAN 
BoTanists became greatly excited when, several years ago, Treub 
published an account of his discovery of Chalazogamy in Casuarina. 
By this term, as our readers may remember (see Natural Science, 
vol, i., p. 132) he described a method of pollination, in which the 
pollen-tube entered the ovule through the chalaza instead of at the 
micropyle. Treub was so much impressed with the importance of 
this and other deviations from the normal course of events in 
Casuarina that he separated it from the rest of the seed-plants under 
the name Chalazogamae, the latter, in which presumably pollination 
was effected through the micropyle, forming the Porogamae. More 
recent work has shown this revision of our classification to be un- 
necessary, and that Casuarina, though certainly presenting remark- 
able anomalies, must still be retained among Dicotyledonous Angio- 
sperms. 
There has recently come from the far East news, and confirma- 
tion of the news, of a yet more startling discovery. 8S. Ikeno and 
S. Hirase, working at Tokyo in Japan, have found that in the pro- 
cess of fertilisation in Cycas and Gingko the male element (generative 
nucleus) is converted before its escape from the pollen-tube, into a 
motile spermatozoid. This swims through a quantity of sap oceurr- 
ing in these genera between the embryo sac and the top of the 
nucleus which forms a thin papery covering for the contents of the 
ovule, and impregnation of the oosphere is therefore effected in the 
same manner as in the Vascular Cryptogams. The spermatozoids 
are much larger than hitherto known among the Cryptogams, and that 
of Cycas is larger than that of Gingko. The shape is oval. The head 
consists of three spiral windings in Gingko, and of four in Cycas, and 
bears numerous motile cilia. The great importance of the discovery 
of the Japanese botanists lies in the fact that it strengthens our 
present system of classification. Hofmeister showed the near rela- 
tion subsisting between Gymnosperms and Vascular Cryptogams 
working chiefly from the development of the female spore (embryo- 
sac) and the structures resulting therefrom. Now from the male 
side comes a striking confirmation of his conelusions,—a confirma- 
