TE Physiology. - 891 
sively vegetable diet. The green color so common in birds is 
due to an admixture of a yellow pigment (Psittacofulvine Kru- 
kenberg) with a dark brown one; and Herr Krukenberg states 
that no blue, white, or green pigment can be found among the 
parrots. He believes that all the darker pigments are derived 
from one substance, probably identical with Coriosulphurine, 
which is thus the most widely spread pigment in birds’ feathers 
The spring birds of Nebraska are enumerated, with notes, by 
A. Hall in Forest and Stream——Mr. H. F. Osborn gives in 
Science, for May 25, the results of an examination of the fetal 
membranes taken from a female opossum which had been cap- 
tured within a few days after impregnation. From this and other 
Specimens and facts, Osborn concludes that the so-called false 
chorion of some of the lower placental mammals in the marsupials 
functions as a true chorion, ż. e. the functions of the allantois in 
the placental mammals are, in a rudimentary way, performed by 
the yelk-sac in the marsupials. “Finally, some genera of the mar- 
Supials probably show the attachment of the allantois to the sub- 
zonal membrane, which is the first step towards the establishment 
of an allantoic placenta.” 
PHYSIOLOGY." 
Locomotor System or Mepus#.—Mr. G. J. Romanes con- 
cludes his observations of the locomotor system of Meduse— 
observations which throw a new light upon rhythmic action gen- 
erally. He believes rhythmic action to be a primary endowment 
of contractile tissue, the excitability of which under the constant 
stimulation of the element it exists in is alternately exhausted 
and restored. The action of ganglia is superimposed on this, and 
is timed so as to coincide with the normal pulsatile action of the 
muscular tissue. Muscular tones he attributes to a higher irrita- 
bility in the structure than is possessed by rhythmic tissues. 
Tue Ortcix oF Fat in THE Bopy.—In Pfliiger’s Archiv, Bd. 
31, P. 11, Dr. Lebedeff tries to show that the common view 
t May arise in the body as a decomposition product of albu- 
minous matter, is erroneous. Dead bodies, under certain condi- 
* This department is edited by Professor HENRY SEWALL, of Ann Arbor, Michigan. 
VOL, XVII.—No,. VIII 60 
