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have their origin in these accumulations of pigment. On the dorsal side, 
this design passes gradually into a more or less diffuse pigmentation. 
The pigmentation however is not regularly diffuse on the dorsal 
Fig. 1. 
side, and especially not on the flanks of the bodies of the larvae. 
It is evident that the “cellstreams”’, described by Hacker for 
the first time, are of importance for the pigmentation. The “cell- 
streams” were very obvious and strongly developed in the skin 
of the Megalobatrachus larvae, in a similar way as Hacker found 
them in Axolotl. These cellstreams are series of cells, which, 
radiating from special centra, divide more quickly and shove in between 
other groups of cells. Thus they form regions of mòreintensely growing 
skin. (Fig. 2). This also seems to coincide with the distribution 
of pigment. I generally noticed that cellstreams radiated obliquely 
backwards from the well-known lateral sense organs. The pigment 
appears first close to the lateral sense-organs on the flanks of the 
