584 The American Naturalist. fJuly, 
scriptions are quite inadequate, and the specimens will have to be more 
fully described before their characters can be sufficiently known. 
The third volume is chiefly occupied with the Edentata, and this 
memoir is admirably illustrated. The descriptions (by Dr. Lydekker) 
are rather more full than those of Vol. II, but not full enough. They 
are marred by frequent supercilious references to Dr. Florentino Ameg- 
hino, who is the most competent paleontologist of the vertebrata in 
South America, and whose descriptions compare very favorably with 
those of other paleontologists in all respects. His figures are not so 
good as those of the work now under review, for here we have a case 
in which the most skilful hand has not had the financial advantages it 
ought to have had. From our past experience we should say that when 
Dr. Lydekker states that organic forms are distinct species he is apt 
to be correct; but when he identifies forms alleged to be distinct, 
further examination is in order.—C, 
BOTANY? 
Tilden’s American Algæ.—The first century of this distribu- 
tion by Josephine Tilden, of Minneapolis, was sent out about a year 
ago, but has not hitherto been noticed in these pages. The specimens 
are very neatly prepared, and are attached to cards or mica slips. In 
most cases they contain an abundance of material, but, in a few in- 
stances, we might wish for more generous specimens. The species 
represent the following genera: 
`. Oedogonium (4), Sphaeroplea (1), Hormiscia (2), Chaetophora (4), 
Drigtirndbilta (3), Stigeoclonium (6), Conferva (1), Microspora (1), 
Urospora (1), Cladophora (15), Pithophora (1), Vaucheria (5), Botry- 
dium (1), Hydrodictyon (1), Tetraspora (2), Palmella (1), Protococcus 
(3), Euglena (1), Spirogyra (10), Cosmarium (1), Porphyrosiphon (1); 
Symploea (2), Lyngbya (2), Phormidiwn (1), Oscillatoria (8), Spirulina 
- (1), Gloeotrichia (2), Tolypothriz (1), Nostoc (8), Anabaena (2), Meris- 
mopedia (1), Navicula (1), Pleurosigma (1), Gomphonema (2), Coc- 
` coneis (1), Nitzschia (1), Odontidium (1), Synedra (2), Fragilaria (1), 
‘Cystopleura’ (1), Lysigonium (1). ` 
The introduction of Euglena among plants is, in our opinion, a mis- 
take, although one which will probably do ‘no harm, since it will be 
difficult if not impossible to` recognize them from dried specimens. ove 
i Edited by Prof. C. E. Bessey, University of Nebraska, Lincoln, Nebraska. 
