49 
nium in which the occipital region represents a multiplum 
of vertebrae, not one vertebra as is rendered probable by 
ontogeny, by the absence of occipital nerves and by 
the fact that the anterior spinal nerves innervate the 
hypobranchial musculature. FüRBRINGER himself, as we 
have seen (cf. p 285), recognizes that no facts can be adduced 
in favour of this supposition. He only mentions (1. c. p. 486) 
that once, in a young Megalobatrachus, he believes he has 
found an extremely fine nerve-thread in the occipital region. 
He considers it as a last remnant of more such nerves and 
calls it zZ but does not feel quite sure of his observation 
which, however, has been afterwards confirmed for embryo- 
nal stages of different Amphibia. OSAWA (1902) found it in 
ed Caps. audt, 
" Froc. tie 5 
Prlatoguadr 
lars articul. 
Fig. 21. Rudiment of the skull of Siredon pisciformis. Arc. occ. occipital 
arch, Caps. audit. auditory capsule, after STÖHR, 1879. 
Megalobatrachus, DRÜNER (1901, 1904) in larvae of Triton 
ad Salamandra, PETER (1898, p. 42) and MARCUS (1910, 
p. 376) in Gymnophiones and GOODRICH (1911) in Siredon. 
At the end of this chapter we shall revert to this nerve and 
show that it evidently represents the ventral root of the spinal 
nerve of which the ganglion has fused with that of the primary 
vagus (the “spinalartiger Vagusanhang”’ of _HATSCHEK, 
1892) and corresponds to FüRBRINGER's occipital nerve x 
in Selachians like Scyllium 
LXXXII 
