166 Dr. R. Leuckart on the Asexual Reproduction 
90-045 millim. without giving any signs of further development 
(fig. 5), unless we regard as such the enlargement of the central 
nuclei (to 0-01 and 0-014 millim.) and the more distinet ap- 
pearance of a clear vesicular nucleolus. 
' But when the germ-ball has attained the size just mentioned, 
we observe that one of the eight or ten clear nuclei contained in 
it surrounds itself with a strong accumulation of coarsely gra- 
nular protoplasmic mass, and inflates the peripheral envelope of 
the ball like a hump (fig. 6). At first only of meonsiderable size, 
this hump gradually becomes larger with’ the increasing growth 
of the granular mass, so that the ball loses its globular form and 
gradually acquires a pyriform aud oval shape (figs. 7&8). The 
mass of granules situated in the interior of the smaller pole, and 
filling this entirely, becomes more and more sharply discrimi- 
nated from the other contents of the ball, and gradually grows 
into an independent body, the previous relations of which one 
could hardly indicate without a knowledge of its development. 
The increase of this body takes place so rapidly that in a germ- 
ball of 0-077 millim. in length (0-042 millim. in breadth) it 
already measures 0-03 millim., and therefore has almost attained 
the size of the whole of the rest of the contents (fig. 8), although 
a little while before (in balls of 0:06 millim. in length and 0-038 
millim. in breadth, fig. 7) it had scarcely more than half this 
diameter (0-018 millim.). And this increase of size is the more 
remarkable, becanse it depends solely on the growth of the gra- 
nular peripheral mass, the vesicular nucleus still measuring not 
more than 0:014 millim. The latter has, however, so far un- 
dergone a change, that the nucleolus contained in it has become 
smaller (down to 0-004 millim.) and acquired a sharper outline. 
Although, from the dark and opaque texture of the granular 
mass, the processes here described readily attract the attention of 
the observer, they have been as good as completely overlooked by 
previous investigators*—a fact which can only be explained on 
the supposition that they were more interested in the subsequent 
fate of the germ-balls than in their earlier states. 
Notwithstanding their neglect on the part of former observers, 
these processes are now of great significance, inasmuch as they 
throw an unexpected light upon the nature of the germ-balls, 
and the relations of the present mode of increase to the ordinary 
reproduction of insects. 
geneous mass of which some strongly defined and rather angular oil- 
granules and vesicular vacuoles appear.” 
* The only indication of them is a figure of Wagner’s (J. ¢. tab. 36. 
fig. 25), which is explained as representing ‘‘two anomalously united 
germs (Hmbryonaltheile),” of which one is filled with a turbid fluid, whilst 
cells are already formed in the clear contents of the other. 
