PRIMROSE : THE ANATOMY OF THE ORANG OUTANG 
89 
EXPLANATION OF PLATES. 
The following plates are drawings from dissections made by the author : — 
PLATE III. 
Pig. I. — Dissection of the posterior aspect of the neck and shoulder of the Orang 
Outang. 
acrom,^ acromion process ; clav..^ clavicle ; e.a.m.y external auditory meatus ; 
i.spin.y infra spinatus ; l.a.s., levator anguli scapulae ; m,o.y omo cervicalis; 
rhont.y rhomboid ; s. spin., supra spinatus ; s. mag.y serratus magnus ; 
trap.y trapezius ; t. min., teres minor. 
PLATE IV. 
Fig. 2. — Dissection of the anterior aspect of the chest wall and shoulder of the Orang 
Outang. 
acrom., acromion process ; clav., clavicle ; cor., coracoid process ; Belt., 
deltoid ; H., humerus ; p. min., pectoralis minor ; p. m. i, the pars costo- 
abdominalis of the pectoralis major ; p. 77 i. 2, the pars sterno-costalis of the 
pectoralis major ; p.771. 3, the pars sternalis of the pectoralis major. S. 771., 
sterno mastoid. 
Fig. 3. — Representation of the mode of insertion of the pectoralis minor muscle. 
acro 77 i,, acromion process ; clav., clavicle ; cor., coracoid process ; lig. i and 
lig. 2, continuation of the fibres of insertion of the pectoralis minor muscle 
into the clavicle and the acromion process ; p. min., the tendon of insertion 
of the pectoralis minor muscle passing to the coracoid process. 
Fig. 4. — The arrangement of the interossei muscles in the Orang Outang, as they 
appear in their relation to the metacarpal bones, on transverse section 
through the metacarpus. 
d. i., dorsal interossei ; v. i., palmar interossei. 
PLATE V. 
Fig. 5. — Dissection of the short muscles of the thumb and the little finger in the Orang 
Outang. 
ab.77i.d., abductor minimi digiti ; ab.P., abductor pollicis ; ad.o.p., adductor 
obliquus pollicis ; a.t.p., adductor transversus pollicis ; F., palmar fascia ; 
f.b.p. i,fb.p. 2, outer and inner heads of the flexor brevis pollicis ; fi.b.7n.d., 
flexor brevis minimi digiti ; op. 771 . d., opponens minimi digiti; o.p., opponens 
pollicis. 
Fig. 6. — Dissection of the interossei muscles of the hand in the Orang Outang, viewed 
from the palmar aspect. 
v.i. I, v.i. 2, v.i. 3, palmar interossei, d.i,i, d.i. 2, d.i.'^, d.i.o^, dorsal interossei. 
