392 
EDWARD PHELPS ALLIS. 
branchial rays aborted, slipped onto the posterior, instead of 
onto the anterior, surface of the cartilaginous bar of the arch, 
and so, not crossing that bar, was not cut in two as the other 
fibres of the constrictor were. 
In certain other Batoidei, the musculus spiracularis is said 
by Luther to have a less extensive ventral prolongation than 
in Astrape, being said to extend either to the ventral end of 
the hyomandibula, to the abdental edge of the mandibula, to 
the ceratohyal, or to the dorsal fascia of the musculus coraco- 
mandibularis. In Astrape and Torpedo, certain fibres of the 
muscle are said to be inserted on, and others to arise from, 
the spiracular cartilage, that cartilage thus lying between 
dorsal and ventral portions of the muscle; and as I have 
lately shown (Allis, 1915) that this cartilage of these fishes is 
quite certainly the dorsal extrabranchial of the mandibular 
arch, the muscle thus has the relations to this cartilage that 
the branchial constrictores superficiales of certain Selachii 
have to the dorsal extrabranchials of their respective 
arches. 
Other portions of the primitive constrictor apparently lost 
only their ventral, intermandibularis, portion, retaining their 
full lengths dorsal to that muscle. Such portions are 
apparently found in the second and third divisions of the 
levator maxillse superioris of my descriptions of Amia, and in 
the levator labii superioris of certain of the Batoidei, all of 
which muscles extend, with their tendinous ends, from the 
neurocranium to the abdental edge of the mandibula. The 
levator labii superioris of the Batoidei, called by Luther the 
musculus prmorbitalis, is said by that author to usually extend 
only to the angle of the gape of the mouth and to there be 
inserted in the aponeurotic septum of the adductor mandi- 
bulse, but it may have a ventral ligamentous prolongation, or 
even a large muscle belly, which extends beyond the angle of 
the gape and is inserted, with the mandibular portion of the 
adductor, on the mandibula. In certain of the Batoidei it is 
even said that the tendinous ventral end of the muscle is 
practically continuous with the lateral edge, and hence 
