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pharynx musculature and the musculus cricothyroideus, the nervus 
laryngeus superior and the nervus laryngeus inferior (recurrens) 
rise from one stem, in such a way that this stem soon divides into 
two branches, one of which splits into the two first-named nerves, 
and a third descending branch, which gives off a ramus oesophagaeus, 
besides the nervus laryngeus inferior. This last describes a slight 
curve before reaching the larynx, is thus also recurrent, though not 
in the ordinary sense of the word. 
This unusual course of the nervus recurrens is quite contrary to 
what has been hitherto assumed in favour of the phylogenetic and 
ontogenetic development of this portion of the periferal nervous system. 
In amphibians, which possess only one cervical vertebra, the heart 
is situated caudo-ventrally from the larynx. The nervi laryngei 
inferiores reach the larynx behind the large blood-vessels which come 
from the heart. With the development of the neck, the heart changes 
its place in a caudal direction and causes the above-mentioned nerves 
to descend with it ana to reach their territory of innervation by a 
long recurrent course. Lespre, who in his detailed treatise, gives a 
very clear illustration of the devious course of these nerves in 
Camelidae, is of opinion that the ordinary recurrent course of the 
nervi laryngei inferiores has been sacrificed to the unusual length of 
neck in these animals, and expresses the desirability of investigations 
as to whether similar differences are to be seen in the giraffe. 
This fact, meanwhile, implies that the nervus laryngeus inferior 
in Camelidae has much less to do than in other animals which 
possess a genuine recurrens in which also more elements are joined. 
Of both Camelidae the vagus area was cut serially into sections 
of 18 microns; that of the camel was coloured with eresyl-violet 
and that of the lama with toluidineblue. 
Camelus bactrianus. The region of the dorsal motor vagus nucleus 
is cut into a series of 571 sections, of which 365 are spinal and 
206 frontal from the calamus, so that, as in the goat about */, of 
the nucleus lie in the closed portion and ?/, in the open part of 
the oblongata (fig. 1). The nucleus begins caudally as a narrow 
horizontal row of cells, dorso-lateral from the canalis centr. in a 
region where the anterior horns of the eervical cord are still in 
full development. The nucleus increases slowly, and principally at 
its lateral side; 70 sections more frontally, before any distinet cells 
of nucleus XII are present, we see also the medial side becoming 
slightly thicker, and in the bridge which connects the nuclei right 
and left, dorsally from the central canal, a few cells oceur, of the 
