The integument and subcutaneous cellular membrane of this region differ but little from the same structures in the occipito-frontal re gion. The former is finer and not so thick as in the middle and posterior parts of the last named region. The hairs are oblique, some directed forwards, others backwards towards the occiput, and others downwards overlap ping the ears. IIere the hairs first begin to grow grey, whence the denomination tempora has been applied to these regions, grey hairs marking the inroads of time. The skin of this region, however, is naturally bald for a consi derable portion in front of the ear, and for the distance of about an inch immediately behind and above it.
The subcutaneous cellular tissue is very loose in front of the ear, but behind it in the vicinity of the mastoid process, it is more dense, and hence the scalp is much less move able over that process, and immediately be hind the ear. The epicranial aponeurosis is confounded with this subcutaneous tissue in the superior part of this region.
Temporal to the cellular expansion is a fibrous membrane of consider able strength, which stretches from the zygoma below to the curved line above and behind which limits the temporal fossa on the frontal, parietal, and temporal bones. It is very thick and strong, composed of white interlacing fi bres, firmly attached to the points of bone referred to, and giving attachment by the greater part of its deep surface to the fibres of the temporal muscle. In front and below, however, for a, short space, some adipose cel lular membrane intervenes between the muscle and the fascia. Along the margin of the zy goma, especially in front, the fascia is divisible into two laminx, which pass down, one in ternal, the other external to the bone, and become incorporated with periosteum: by their separation above the zygoma they leave a tri angular space which is in general filled with cellular tissue more or less adipose.
fibres of the occipito frontalis extend more or less into this region, according to the state of developement of the mUscle. IIere too we find the three auricular muscles immediately subjacent to the subcu taneous cellular tissue. (See EAr..) Under the temporal fascia and adhering to its deep surface is the fleshy portion of the temporal muscle, attached to almost the whole of the fossa. Behind, the mastoid process is enveloped by. the tendinous insertion of the sterno-mastoid muscle.
nerves of this region are very numerous. The subcutaneous ones are derived from the portio dura and the superficial tem poral or auricular of the fifth, and posteriorly from the mastoid and digastric branches of the portio dura, as well as some from the ascending branches of the cervical plexus. The deep
seated nerves in the temporal fossa are the deep temporals from the inferior maxillary, and the temporal filament of the orbitar branch of the superior maxillary.
superficial arteries are nu merous and important. They are derived from the trunk of the superficial temporal, which enters this region by passing over the zygoma in front of the tracrus, crossed over by the anterior auris muscle. After it has passed the zygoma it inclines forwards, and is a little mom distant from the ear than when on tbe zygoma. In all this course it may be felt distinctly, although it is pretty firmly bound down by the subcutaneous tissue and epicranial aponeurosis, which are here conjoined. A little more than an inch above the zygoma it divides, and we trace its anterior branch forwards towards the frontal region, which it enters and anastomoses with the supra-orbital. The posterior branch passes upwards and backwards, winding over the ear, and anastomoses with ramifications from the occipital artery. It is in one or other of.these branches that arteriotomy is generally performed, in preference to opening the trunk of the artery. The middle branch of the temporal artery pierces the fascia, and enters the substance of the tem poral muscle anastomosing with the deep temporals. The posterior part of this region is supplied from branches of the occipital and posterior auris.
accompany almost all the arteries : there are none worthy of any special notice.
vessels likewise accom pany the arteries, and enter the ganglions in the neighbourhood of the ear, and those of the neck.
pericra,nium does not differ from that of the occipito-frontal region, except perhaps in firmer adhesion to the squa mous portion of the temporal bone. It affords insertion to the fibres of the temporal muscle. This region presents more surgical interest than the former one ; it is more fre quently the seat of operation (arteriotomy, and in its posterior part, that of opening the mastoid cells); and in consequence of the number of its arteries and nerves, and the great strength of the tempoml fascia, wounds in this region are of a more dangerous kind. Fractures here are also liable to be complicated with a wound of the middle meningeal artery, part of the course of which corresponds to this region.
( R. B. Todd.)