THE SENSES. 263 



eye, for rect. super, and infer, rather inwards of the vertical diameter (Wil- 

 brand). Use : each draws the globe towards its own side ; associated they 

 draw it inwards, with the exception of the rect. extern. [The rect. externus 

 has two origins, one as stated, the second from the margin of the spheroidal 

 fissure.] 



Rectus superiors, superbus is the weakest ; rect. inferior s. humilis: rect. 

 internus s. amatorius s. bibitorius, the shortest and thickest ; rectus externus 

 8. indignatorius, antagonist of the two obliqui, the longest, is alone provided 

 by nerv. abducens, the others by N. oculo-motorius. 



c. M. obliquus superior s. trochkaris s. patheticus. 



Or. : between m. rectus sup. and intern, before the foram. opticum, from 

 the body of the Sphenoid bone. Ins. : at the superior part of the Sclerotica; 

 four lines broad, behind muse. rect. super. Figure : elongated, fusiform ; the 

 tendon curves backwards, .downwards, and outwards. Position : at the 

 superior, internal angle of the orbits ; the tendon passes in the trochlea [a 

 small cartilage, five-sixths of a small ring] through a tendinous sheath. It 

 is alone provided by nerv. trochlearis. Use : to roll the globe inwards and 

 downwards. 



d. M. obliquus inferior s. minor. 



Or.: os maxilar super., between mar go infer, orbitae [sometimes from it] 

 and canal, lacrymal. ; often from the lacrymal sac. Ins. : the posterior ex- 

 ternal part of Sclerotic, six lines distant from the cornea, three from the optic 

 nerve, behind the attachment of rectus externus. Pos. : flat under the globe 

 of the eye (externally, above and behind) between the floor of the orbit and 

 m. rectus inferior, enveloped in fat. Use : to roll the bulbus outwards and 

 upwards. Both muse, obliqui draw the globe forwards [?] . 



496. B. The Globe of the Eye, Bulbus oculi, 



an oblong globe formed of three circular membranous layers lying 

 over one another, which are filled with a transparent refracting ap- 

 paratus, being surrounded by the capsule of the eye and an elastic 

 cushion of adipose tissue in the anterior parts of the orbits, and 

 projecting outwards at the external border of the basis beyond it. 

 Its longitudinal diameter is about one line longer (eleven lines) than 

 the transverse, as the anterior segment of the globe formed by the 

 cornea projects before that composed of the Sclerotica. 



Capsula bulbi oculi (Bonnet and Ferrall), 



a strong, fibrous membrane, firmly applied behind to the globe, and 

 passing, becoming thinner in its course, into the fibrous sheath of 

 the Optic nerve, before into the Perichondrium of the tarsi of both 

 eyelids. All the muscles of the globe lie behind and perforate it 



