No. 400.] REVIEWS OF RECENT LITERATURE. 329 
factors than the lack of conjugation, and that we do not yet know 
any limit to the length of life these creatures may have under proper 
conditions. EX X 
Swiss Infusoria. — The school of Swiss zoólogists at Geneva, 
undtr the able leadership of Professor Yung, has in recent years 
shown great activity in the investigation of the local fauna. This 
work has been of high order and is abundantly illustrated with litho- 
graphed plates. That an interest in the Infusoria would still linger 
in the home of Claparéde is indeed to be expected, though a list of 
new genera and species of Ciliata from the environs of Geneva 
comes as a surprise. Nevertheless Dr. J. Roux has discovered there 
a dozen new ciliates whose structure and relationships he discusses 
at length in a recent paper.’ He also describes and fully figures 
a score of other forms concerning which his studies have added 
important information. Of prime interest is his Monomastix ciliatus 
— a new member of the Mastigotricha which combines characters 
of the Ciliata and Flagellata, having the cilia and nuclear conditions 
of the former and the flagellum of the latter. An amplified descrip- 
tion is given of Zionotus vesiculosus Stokes, originally described as 
from this country. The discussion of Loxodes rostrum sheds light on 
a number of controverted points; the animal is flattened dorso-ven- 
trally, not laterally, and the peristome is ventral, though placed 
to the left, being bordered by fine cilia and transverse stria which 
have heretofore been interpreted as long cilia. The genus should 
be removed from the Trachelina to a new family, Loxodina. Various 
American species of this genus have been ill-founded, resting merely 
on inconstant variations in color, number of nuclei, and excretory 
vacuoles. On account of its superb illustrations and the critical 
Character of the discussions, this paper is of especial value to all 
American workers in this much neglected group, and it is to be 
hoped that Dr. Roux will continue his studies. CO AU. 
Growth in the Rhizopodan Shell, after its formation at the 
time of the division of the parent, as acs by Rhumbler, is 
contested by Penard in a recent paper.? In observed cases in a 
! Roux, J. Observations sur quelques ciliés des Environs de Genéve, avec la 
description de nouvelles espéces. Rev. Suisse de Zoöl., tome vi, pp. 557-636, Pls. 
XIII, XIV, 1 1899. 
?Penard, E. Sur la croissance supposée de la coquille chez les Thécame- 
biens. Arch. Sci. Phys. et Nat., IV Pér., tome vii, 23 pp., 1899. 
