No. 393.] REVIEWS OF RECENT LITERATURE. 747 
stowia, while resembling the different groups of the genus Bertia, in 
individual respects, is yet relatively furthest removed from that 
group which is found in marsupials. 
In a summary the author notes that all Tæniæ at present known 
from aplacental mammals belong to the subfamily Anoplocephaline, 
which is typical for herbivors, and are found in three genera, Monie- 
zia, Bertia, Linstowia. Between the Anoplocephaline of placental 
and aplacental mammals there exists a certain anatomical parallel, 
corresponding to the similarity in their manner of life and nutrition. 
Pure herbivors, such as ruminants and the giant kangaroo, harbor 
the genus Moniezia. The marsupials, Phascolarctus, Phalanger, as 
also the placental Galeopithecus, live on leaves, fruits, and rarely also 
on insects; in them is parasitic a well-circumscribed subgroup of 
the genus Bertia. Finally the aplacental insectivors, Echidna and 
Perameles, are inhabited by a special genus Linstowia, for which a 
parallel from Placentalia is not at present known. HBW 
Histology and Physiology of the Gastræadæ.— Under this head 
T. Garbowski ' describes the results of some recent observations on 
Trichoplax adherens F. E. Schulze, on which he bases certain 
theoretical conclusions, 
He finds the body epithelia covered with a several-layered cuticle, 
through which project the cilia. Contrary to the statement of 
Schneider, these cilia are not continuous within the cytoplasm, but, 
as is shown by impregnation with gold chlorid, are merely outer proc- 
esses of the cells. It is conclusively shown that the ventral epithelium 
possesses no digestive power. This function is assumed by certain 
cells of the loose body parenchyma. Undoubtedly only liquid food 
is assimilated, chiefly organic decomposition products. Other cells 
of the parenchyma, becoming fibrous in character, take a dorso-ventral 
arrangement and act as muscles. The so-called muscles of von Graff 
appear as artifacts under the action of certain chemical reagents. 
The large spheres, regularly arranged in the parenchyma and 
usually described as fat bodies, are shown to be the intercellular 
excretory products of the animal and are closely comparable to the 
excretory vacuoles of the larger amcebx. Those other yellowish 
brown globules, which have been variously interpreted as otoliths, 
spermatoblasts, etc., are more probably specimens of a symbiotic 
alga, Zooxanthella. 
1 Zur Histologie und Physiologie der Gastraeaden, Bull. Internat. de L'Académie 
des Sciences de Cracovie, February, 1899, pp. 87-98. 
