912 The American Naturalist. [October, 
hundred species taken in order, in Saccarda's Sylloge Fungorum, shows 
fifty-five to be hypophyllous, thirty amphigenous, and fifteen epiphyllous, 
the proportion of amphigenous species having sHghtly increased. We also 
notice here a decided increase in epiphyllous species. This may likely 
be accounted for from its being an intermediate stage, springing from 
the germination of the agcidiaspores. These, produced, as we have 
seen, with but few exceptions, on the lower surface of the leaf, would 
tend to drop their spores on the upper surface of the leaves below them, 
thus perhaps giving rise to this more frequent epiphyllous character of 
In the teleutospore stage of species in Burrill's Uredineae (Puccinia, 
Uromyces, etc.), the amphigenous species predominate by a small 
The increasing frequency of amphigenous position from the first 
stage to the last thus seems to be due to the older and more extensive 
growth of the fungus in the tissue of the host. Its continued growth 
likely injures and somewhat softens the upper more firm palisade tissue, 
thus allowing a breaking out above. — Herbert A. Webber, Lincoln, 
Neb. 
ZOOLOGY. 
Gastrotricha.— Carl Zelinka, of Gratz, has recently monographed 
the Gastrotricha of the world {Zeitschr. wiss. Zool, XLIX., Pt. 2, 
1889). These are small aquatic forms the position of which is very 
uncertain. They are defined by Zelinka as follows : Without retract- 
ile ciliated wheels on the anterior end ; with two ciliated bands extend- 
ing the length of the ventral surface ; with two coiled water-vascular 
canals each bearing a rod-like ciliated funnel and terminating separ- 
ately on the ventral surface ; a simple brain, not completely separate 
from the ectoderm ; simple muscle cells ; paired ovaries ; fore-gut 
muscular, Nematode-like, without jaws, with straight glandless mid-gut 
and pear-shaped hind-gut, rectum and dorsal anus ; with primary body 
cavity. With these points Zelinka is inclined to place them near the 
Rotifiers. He describes the anatomy, dealing especially with the skin 
and its appendages (scales, hairs, etc.), water-vascular system, nervous 
system, sense organs (tactile hairs, eye spots ?), muscular system, ali- 
mentary tract, and genital organs. In all, thirty-two species are 
enumerated. The following key serves to separate the genera : 
