170 Recent Literature. | February, 
than that at any other point, consequently the ovulum at this 
_ point passes out, drawing with it the pedicel of protoplasm which 
still remains in connection with the central mass, which Will calls 
the “rachis,” and which corresponds to the rachis in the nema 
todes. The ovules have now a chance to grow again, and when 
the pressure is again exerted another passes out. ; 
(2) In a similar way the growth of the young egg is explained 
The ovula as well as the young eggs being connected with the 
rachis by a string of protoplasm they cannot be considered a 
distinct cells, for it must be considered that the protoplasm 15 
common to all the cells. It is evident that the new protoplasm 
which the egg and ovula acquire by a process of assimilation 5 
common as well. The pressure exerted upon the epithelial layer 
of the egg is not as great as that upon the wall of the termi 
chamber and consequently there is much less pressure on the egg 
than on the ovula. Owing to the great pressure on the ov 
the growth is not so rapid as in the egg, consequently uch 
the common protoplasm of the terminal chamber goes 
nourishment of the egg through its pedicel. cells 
The cells of the terminal chamber not being vitelligenou® ik 
but ovula, the pedicel is consequently not for the passag® of yo 
but protoplasm. 4 
TI. Formation of the Blastoderm,—~The young ¢€gg) which po* 
sesses no membrane at all, consists of a very homo eneous Pa 
toplasm. The clear germinal vesicle (keimbläschen) does ! 
take any color in carmine, while the dense germinal spot (kell 
y examining large numbers of eggs in the first stages of de 
velopment Will finds that the germinal vesicle does not disappet: 
The first change consists in the appearance of a great no 
little vesicles of deutoplasm which are quite different from 
later fully developed deutoplasm called by Metschnikoff gr 
därer dotter.” These vesicles fill up the whole protop ae that 
the exception only of that near the periphery of the egg cs really 
not surrounded by deutoplasm but lies in an irregular E 
protoplasm. In section he found the primitive nuclei in di he 
where they undergo division and form the future cells o! 
blastoderm, The blastoderm consists of a single layer of be- 
which possess a common protoplasm and only later do they 
come separate. The blastoderm does not cover the ex 
face of the egg, for at one pole (the basal), the deut plasm 
tends to the surface of the egg. 
Will differs considerably from A. Brandt as regards 
cell divs 
