1883.] Psychology. 445 
claims that all the organs are formed either directly or indirectly 
it; the mesodermal elements do not arise at any definite and 
ingle. point, and there is no evidence of any cleavage in it, and 
still less of the formation of a true ccelom. As the endoderm, 
so-called, does not give rise to the enteron, its homology with 
the similarly named layer in the chick is to be doubted. 
EARLY DEVELOPMENT OF THE SALP&.—F. Todaro in his second 
preliminary paper, published in the Italian Biological Archives, 
states that he has observed the entrance of a single zoosperm into 
the egg, its conversion into a male pronucleus, and its fusion with 
the female pronucleus to form the segmentation-nucleus, while 
the yolk is derived from the epithelial cells of the ovarian sac. 
The origin of the embryos of the solitary and compound Salpe 
isalso described.— Journal Royal Microscopical Society, Feb., 1883. 
ETO eet eee 
PSYCHOLOGY. 
ANIMAL Doctors.—In a recent communication to the Biologi- 
cal Society, M. G. Delaunay observed that medicine, as practiced 
by animals, is thoroughly empirical; but the same may be said of 
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i ML. Delaunay lays down as a general rule that there is not any 
, *pecies of animal which voluntarily runs the risk of inhaling ema- 
from their habitations; others bury their excrement; others 
__ Garry to a distance the excrement of their young. In this respect 
- er more foresight than man, who retains for years excre- 
i in stationary cesspools, thus originating epidemics. If we 
a petr attention to the question of reproduction, we shall see that 
aiala suckle their young, keep them clean, wean them at 
=? per time and educate them; but these maternal instincts 
fact, gma rudimentary in women of civilized nations. In 
Animals may take a lesson in hygiene from the lower animals. 
Those oth ak rid of their parasites by using dust, mud, clay, &c. 
: anid a; ring from fever restrict their diet, keep quiet, seek dark- 
- Whena nid places, drink water and sometimes even plunge into it. 
88 dog’s og has lost its appetite it eats that species of grass known 
tive, Sh ga (chiendent), which acts as an emetic and purga- 
o tan also grass. Sheep and cows, when ill, seek out 
stances, ş bs. When dogs are constipated they eat fatty sub- 
The ich as 
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deen € thing is observed in horses. An animal suffering from 
; rner 
Cit the <P at Fe regularly organized ambulances. Latreille 
