308 
EDWARD PHELPS ALLIS. 
hyoideus, setzen sich vielmehr nur an sie an, durch eine 
Fascie von ihu getrennt. Der M. coraco-hyoideus ist ein 
echter Korpermuskel, aus den Urwirbeln her stamm end, und 
hat genetisch nichts mit der Visceralbogen-muskulatur zu 
schaffen.” 
The deeper portion of the constrictor superficial^ of Vetter's 
descriptions, above referred to by Dohrn, is simply a bundle 
of the proximal fibres of that muscle, and it is thus said by 
Dohrn to be developed from the proximal portion of the 
ventral end of the myotome of its arch. But Dohrn has 
elsewhere definitely said, as just above stated, that this part 
of the myotome of his embryos becomes the musculus coraco- 
branchialis. These two muscles must then either have been 
considered by Dohrn to be identical, or he overlooked the fact 
that they were both said to be derived from the same part of 
the myotome. The muscle developed from the remaining, 
distal portion of the ventral end of the myotome is not 
specifically named by Dohrn, and although he says that it 
was wrongly called the coracobranchialis by Vetter, he never- 
theless seems to refer to it in a later work (1885) by that 
name, as will be later shown. How he came to the conclusion 
that the coracobranchialis of Vetter’s descriptions of the adult 
was developed from this part of the myotome, and that the 
muscle was wrongly named by Vetter, is not apparent; but it 
would seem as if it must have been because of Vetter’s figure 
of Acanthias, which seems to show the ventral ends of the 
constrictores superficiales wholly wanting excepting as they 
are represented, in the first branchial arch, by a small bundle 
of muscle fibres. Probably misled by this figure, and Vetter’s 
descriptions of it, which give, as will be later shown, an 
incorrect idea of the conditions, Dohrn seems to have con- 
cluded that the ventral ends of the constrictores must also be 
wanting in the adult Scyllium, and as he found, in his 
embryos of that fish, a distal portion of the ventral end of the 
myotome that had to be accounted for, he concluded that it 
must be the coracobranchialis of Vetter’s descriptions of the 
adult. 
