130 
PROFESSOR A. MACALISTER ON THE 
that this muscle is the modified occipital trapezius, because : — 1st, it is supplied by the 
spinal accessory nerve, as I have been able to demonstrate in JElentherura and Cephalotes , 
as well as in Megaderma ; this is the source from which the occipital trapezius draws its 
nervous supply in Man ; had it been platysmal it would have been supplied by the 
branches of the cervical plexus ; 2ndly, it has a more definite origin than any part of 
the panniculus ; ordly, the spot of its origin is exactly that from which the trapezius 
should arise ; 4thly, it is redder than the rest of the superficial muscles ; 5thly, it is ana- 
logous in function to the tensor plicee alaris of the bird, which is the modified acromial 
deltoid, retaining its origin and altered in its insertion ; this seems to be a similarly mo- 
dified occipital trapezius ; 6thly, there is no trace of any other occipital trapezius, and the 
muscle is always highly developed. Against this view is its arrangement in Cephalotes 
and Eleutherura , in which it is actually joined to the cutaneous muscles at its origin. 
The superadded muscular fibres in the forearm may represent an accessory palmaris, a 
palmaris brevis, or a flexor digitorum sublimis. 
The uses of these muscles are very obvious ; the occipito-pollicalis raises and abducts 
the thumb and makes tense the dactylopatagium brevis. If the triceps cooperate with 
it, it makes tense the propatagium ; the three parts of the platysma cooperate with it and 
assist it. The other muscular bands either contract the wing-membrane or move the 
skin. As a general rule the disposition of the cutaneous muscles will be seen to 
resemble closely the arrangement of the panniculus in the higher Carnivora. 
Facial Muscles. 
This group of muscles is very well developed among the Bats, and though paler than 
the body- and limb-muscles, yet they are redder than usual. 
The occipito-frontalis (Plate XIII. figs. 2, d, Sc 6, c, d) in all is quadrigastric, the occipital 
bellies being quadrilateral, parallel, and close together ; this muscle arises from the inner 
third or half of the superior occipital line. In Plecotus the bellies are very short and 
thick, in Cephalotes they are thin and weak ; these soon end in the epicranial aponeu- 
rosis, from which the anterior bellies spring. In Plecotus the aponeurosis begins on the 
level of the base of the ear, and the frontal bellies are inserted into the integument of 
the forehead and into the procerus nasi ; the anterior bellies are confluent in Noctulina , 
as well as in the Bhinolophus diadema and speoris, and are barely separable in Vampy- 
rops and Artibeus, in both of which the posterior bellies have a wide origin. In these 
also the epicranial aponeurosis is narrow, not exceeding in its length one half of the 
width of the ear-cartilage ; the frontal bellies are enormous in Cephalotes, very small in 
Megaderma, moderate in the Pteropidse. 
The size of the ear-muscles, though in general they bear some proportion to the 
development of the auricle, cannot be said to obey any regular law; for while in 
Plecotus and Synotus they are larger than in Vespertilio, Scotophilus, or the Pipistrelle, 
yet in Bhinolophus and Eleutherura they are nearly as large as in Megaderma lyra. 
The extrinsic muscles are the usual three. 
