471 



(h) Posterior Muscles of Sip Joint. 



Grains. 



1. Glutaei, pyriformis, obturatores, and gemelli, 280 



(c) Anterior Muscles of Sip Joint. 



1 . Iliacus and two psoades, 120 



2. Adductores^ ... 220 



{d) Extensors of Knee Joint. 

 1. Quadriceps femoris, 160 



{e) Flexors of Knee Joint. 

 1. Biceps, semimembranosus, semitendiuosus, (and gracilis), . 270 



(/) Other Muscles. 



1. Quadratus lumborum and sacrolumbalis, . 140 



2. Triceps humeri, 125 



3. Latissimus dorsi, 77 



(*12) Accessory slip (wanting). 



(*16) Trachelo-acromius, from transverse processes of atlas and 

 axis, to the posterior edge of the outer third of the clavicle 

 and spine of scapula, . 15 



Sir W. E. Hamilton, LL. D., read a paper— 



OiT THE Eight Imaginary Umbilicau Geneeateices op a Central 

 Surface oe the Second Oedee. 



He stated that lie had been lately led, by quaternions, to perceive that 

 the twelve known umbilics of such a surface are ranged on eight ima- 

 ginary right lines, of which he has assigned the vector equations, and 

 deduced a variety of properties. 



J. Eibton Garstin, Esq., on behalf of Captain St. Yincent Hawkins 

 Whitshed, presented a flat ornamented bronze celt, found near Tallaght, 

 county of Dublin ; also a piece of iron, which was believed to be part of 

 an ancient celt. 



The thanks of the Academy were voted to the donors. 



* These muscles are numbered as in Table II. 



E. I. A, PROC. VOL. VIII. 



