674 The American Naturalist. [July, 
water bacillus from the Thames, B. fluorescens liquefaciens, a pink 
bacterium (probably B. prodigiosus), the hay bacillus, the potato 
bacillus, and various yeasts and other fungi. 
The role of Calcium and Magnesium.—Bokorny seems to 
have proved (Bot. Centrb., 62:1) that Ca and Mg are essential to 
the formation of the necleus and chlorophyll bodies. His experi- 
ments were with Spirogyra, Zygnema, and Mesocarpus in Aluminum 
beakers in distilled water to which nutrient salts were added: 
(1) Ca withheld; (2) Mg withheld; (3) Ca and Mg withheld; (4) 
Complete. The alge were under observation 6 weeks. In 1 there 
was a gradual decided shrinkage of the chlorophyll bands although 
starch continued to form. In 2 the nucleus and pyrenoids also shrank, 
the former to ł natural size or to complete disappearance. In 3 the 
nucleus shrank decidedly and the pyrenoids seemed to become smaller. 
In 4 the cell-organs remained normal and the plants continued bright 
green.—ERwIn F. SMITH. ; 
ZOOLOGY. 
The Faunal Regions of Australia.—At the Adelaide meeting 
of the Australian Association for the Advancement of Science, Mr. 
Hedley gave a brief summary of the views held by leading naturalists 
in regard to the Faunal Regions of Australia, and also presented his 
own. The substance of his remarks were as follows : 
The discrimination of the various provinces into which the Austra- 
lian fauna and flora group themselves has been frequently attempted. 
To the earlier naturalists, from a study of scanty material and with 
little or no personal knowledge of the continent, four divisions of east 
and west, temperate and tropical, seemed natural and sufficient. Hor- 
ker’s “ Essay on the Australian Flora ” paved the way for a better un- 
derstanding of the relations which various localities bore to each other. 
Owing to fundamental errors of his interpretation of Australian Geol- 
ogy, Wallace’s treatment of the subject in “ Island Life” is of but slight 
value. To the writer, the most successful arrangement of the various 
biological regions yet proposed is that sketched by Prof. Tate, in his 
address to the first meeting of this Association. The author accepts 
two main biological divisions—the Autochthonian, developed in west 
