136 
with its length (a disposition not indicated in the figure). The 
function of this muscle is evidently to elevate the styliform process. 
The spinoso-semianularis posterior (IX), a relatively broad sheet of 
muscle, lies behind the foregoing muscle. It is attached above to the 
upper lateral surface of the anterior dorsal cartilage along the middle 
third of its length, and below to the entire upper edge of the styli- 
form, its insertion being internal to that of the spinoso-semianularis 
anterior. Its function is identical with that of the last-named muscle. 
Behind the spinoso-semianularis posterior lies a muscle of similar 
shape (X) though smaller, which I am not aware that P. FÜRBRINGER 
has named.) It is attached dorsally both to the pedicle of the anterior 
dorsal cartilage and also to the ventro-lateral surface of the posterior 
dorsal cartilage for about the middle third of its length, and ventrally 
to the outer posterior surface of the anterior lateral cartilage. Fol- 
lowing P. FÜRBRINGER's system of nomenclature this muscle may be 
termed the Jatero-semianularis. Its function is apparently to lift up 
the anterior lateral cartilage and so to aid in the distension of the 
throat cavity. In this figure 20 the basilaris muscle (VII) of one 
side of the head is shown in its full extent. This complicated paired 
muscle is well described by P. FÜRBRINGER, hence I shall content myself 
with stating briefly its attachments and principal function. In front 
of the eye it is attached anteriorly and dorsally to the postero-lateral 
outer surface of the posterior dorsal cartilage and to the outer surface 
of the posterior lateral cartilage. In the region adjacent to the eye 
it is attached to the subocular arch, styloid process and cornual 
cartilage. Ventrally the muscle appears at first sight to be continuous 
with the basilaris of the other side of the head but in no region of 
the head is this the case. Series of transverse sections through the 
head (figs. 35—37) show that in a transverse section passing im- 
mediately behind the dorsal process of the piston cartilage (fig. 35), 
a band of muscle (XXI) is attached on each side of the head to the 
hind end of this dorsal process. Bach muscular band (which I at 
first mistook for a distinct muscle) extends back in a straight lne 
beneath the pharyngeus muscle (XX) and in the region of the 
1) I have not a copy of P. FÜRBRINGER’s paper with me and am unable to 
secure one now, no zoological library being within reach, hence I am com- 
pelled to rely upon notes taken from his paper two years ago. This “ latero- 
semianularis” muscle may be identical with the portion of the basilaris 
marked B3 by P. FÜRBRINGER. 
