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motor function supplying the voluntary musculature from 
the myotomes. This condition is found in Amphíoxus 
where indeed HATSCHEK (1892, p. 141) and VAN WYHE 
(1893, p. 171) demonstrated that the splanchnic musculature 
is supplied by branches from the dorsal nerve rocts 
(Rami viscerales). The ventral roots, supplying the striate 
musculature, here exhibit a more or less diffuse character, 
each springing with a great number of roots from the medulla. 
ow there is much to be said for the conception that 
the voluntary, striate, musculature is a new acquisition of 
vantr. gangl. chain 
Fig, 4, Transverse section through the trunk of a young 
lygordius, after HATSCHEK, 1878, tig. 89. 
Vertebrates with regard to Annelids, a special differentiation _ 
from part of the smooth musculature of Annelids. From 
here to the conclusion that the ventral nerve roots sup- 
plying the striate muscles are also a new acquisition is only 
one step, and then BALFOUR's original view would still prove 
to be ultimately correct, equally with VAN WYHE's opinion. 
Mausculature and its innervation. — The first beginning of 
the striate longitudinal trunk musculature, of the myotomes, 
can perhaps be already recognized in Annelids. Here we 
can distinguish the ventral and the dorsal longitudinal 
musculature. The rudiment of the former separates very 
distinctly from the rest of the mesoderm and in transverse 
sections reminds one vividly ofthe myotomes of Vertebrates, 
