CAVITY <>! THK (HtlllT 



orbital margin whilst the latter turns backwards, covering the hinder third of the 



globe. 



The nnlrrior Iniiiiini is a well-marked membrane everywhere, but in certain 

 situations it presents special bands of thickening, corresponding to the direct con- 

 tinual ion . forwards of the slieath of each rectu> muscle. Above and below, this 

 lamina spreads out in the form of two large membranes, which are finally applied 

 to the deep surface uf the pal]x'bral fascia; the lower membrane constitutes what 

 has been described as 'the suspensory ligament of the eyeball.' The upjxT mem- 

 brane requires a fuller description, as its distribution is modified by the presence of 

 the levator palpebne muscle. 



The upper part of the sheath of the sii]>enor reetus (along with the adjoining 

 membrane on each side; of it) passes to the deep surface of the levator, to which it 

 closely adheres, and completely ensheat hs this tendon by extending round its 

 borders to its upper surface. The lower part of this levator sheath is applied to the 



Fio. 738. HORIZONTAL SECTION THROUGH LEFT ORIIIT, VIEWED FROM ABOVE. 

 (After von Gerlach. To show check ligaments, etc.) 



TARSUS 



CONJUNCTIVE. FORNIX 

 LACHRYMAL 3LANO 



Palpebral raphe 



External check __ 

 ligament 



OUTER ORBITAL WALL i 9 



External rectua 



ORBICULARIS PALPEBRARUM 



SPACE OCCUPIED BY SUBCOH- 

 JUNCTIVAL TISSUE. AND BY 

 TENON'S CAPSULE FURTHER 

 BACK 



Upper part of Homer 1 * 

 muscle 



Palpebral faacta 

 Internal check ligament 



TENON'S SPACE 

 INNER WALL OF ORBIT 

 Ol'TIC XEKVE 



Internal rectua 



ETHUOIDAL CELLS 



inferior surface of the deeper of the two divisions of the levator muscle, superior 

 tarsal muscle of Miiller), and is attached to the upper border of the tarsus of the 

 upper lid, reaching laterally to the outer and inner a nicies of the orbit. The upper 

 part of the sheath of the superior tarsal muscle reaches to the middle of the pal- 

 pebral fascia, and is mainly continued forwards between the muscle and the fascia 

 to the anterior surface of the tarsus. 



The lower membrane i-'iu-pensory ligament of the eyeball), joined by the sheath 

 of the inferior reetus. reache< forwards to the attached (hinder) border of the tarsus 

 of the lower lid, where it is mainly attached, while a part of it extends to the lower 

 palpebral fascia. 



To understand the s/wr/V;/ hands of the anterior lamina mentioned above, we 

 must follow the sheath of each reetus muscle forwards, when we find that, while it is 

 rather loosely applied to the muscular l>elly in its posterior two-thirds, it then sud- 

 denly becomes thicker, and is firmly attached to the muscle for some distance before 

 finally leaving it. and is thereafter often accompanied by some muscle-fibres. The 



