* 
1881.] Zoblogy. 59 
but that the different ganglia persist from the larval state. The 
peripheral nerves also persist or survive from the larva to the 
beetle (the species studied was Oryctes nasicornis); besides there 
is an increase in the number, or accession of new nerves different 
from those in the larva, and peculiar to the beetle. 
A punkisubstance, in Leydig's sense, appears to be wanting, as 
also the transverse commissures usually uniting the hemispheres 
of a ganglion. In place of the latter are extraordinarily numerous 
transverse bundles of fibers which, arising from the ganglion cells 
of one side, form the peripheral nerves of the other side, and also 
a bundle which passing through the interlacing of each half of the 
ventral cord, assumes three longitudinal directions. These nerve- 
fibers running parallel to the axis pass continuously from one end 
of the ventral cord to the other, forming in fact the longitudinal 
commissures of the ventral cord. These commissures take their 
origin neither out of a central punktsubstance, nor from a periph- 
eral ganglion mass, but are mere continuations of longitudinal 
nerve-fibers decreasing posteriorly in thickness, and which extend 
through the cesophageal ring commissures to the brain. 
A New Genus or Catrostomipa&.—Prof. D. S. Jordan, informs 
me that the dentition of his genus Chasmis¢es is identical with 
that of Catostomus. The two species from Klamath lake, Oregon, 
described by me under the names of Chasmustes luxatus and C. 
brevirosivis (AMERICAN NATURALIST, 1879, 785), exhibit a different 
type of dentition. The pharyngeal bones are very slender and are» 
flattened, and their teeth are minute and very numerous, as in 
Carpiodes. ‘The genus thus defined will stand in the Catostomine — 
ivision, and next the Budalichthyine, and may be called 
Liromyzon.—E£. D. Cope. 
CeLiutar Irritapiiity.—M. Richet in the Revue Scientifique, 
gives the following synopsis of the effects of stimuli on simple 
animal and vegetable cells. (1) Oxygen is necessary, and there 
is consumption of oxygen during the life of the cellule, (2) The 
intensity of movements grows with the temperature, up to 40° Ce 
above 40° the movements disappear. (3) Neutral solutions 
slightly alkaline are favorable; acid solutions are fatal. (4) All 
change of condition is a stimulant to the cell, and consequently 
provokes its contraction, (§) But this change of condition must 
be abrupt, for, if gradual, it does not provoke reaction. (6) The 
reaction from the stimulus is not sudden, but there is a period of 
“latent excitement” which diminishes in proportion to the in- 
tensity of the excitation. (7) Weak stimulation, powerless when 
isolated, becomes effective when frequently repeated at short in- 
tervals. 
BuppINnc IN Free Mepusa.—The germination of the young 
from the walls of the proboscis of Lzzsta oclopunctata Forbes, 
seems to me to throw some light ona theoretical question of 
