13 
muscle, inserted into mesoscapular spine and metacromion. Here the 
rhomboid stratum is bilaminar, the superficial lamina extending from 
crista occipitalis and ligamentum nuche to posterior angle of scapula 
and the deeper from occipital crest to dorsal part of spine of scapula. 
The part corresponding to the minor rhomboid, however, does not 
share in this delamination, but is separately segmented off posteriorly, 
and joins with its fellow of the opposite side to form a muscular band 
passing between the posterior scapular angles of opposite sides. 
In Yalpa there is only one rhomboid muscle, “ probably the repre- 
sentative of the rhomboideus minor of man.’’* 
In most other Insectivora the rhomboid consists of two parts— 
anterior corresponding to rhomboid cap. and rhomboid major, and 
posterior corresponding to rhomboid minor. Acromiotrachelien is 
generally single and inserted into acromion or metacromion, in Tenrec 
and Hedgehog along with trapezius. 
In Agouti, Mivart and Murie{ describe only “ one continuous sheet 
of rhomboid muscle arising from the paramastoid process of the occi- 
put, the median line of the neck, and the dowsal vertebree.’’ So also in 
Aystiix.§ 
In other rodents the three rhomboid elements are usually present 
and distinct. 
Acromiotrachelien in the Hare|| is inserted with the humeral fibres 
of the trapezius, and in Agoutif in addition partly into the aponeurosis 
of the arm.** 
Amongst the Carnivora the rhomboid sheet may have the three 
factors represented as a single sheet (Procyon), or they may be distinct. 
In the Dog and others the occipital portion seems to be absent. + 
The acromiotrachelien is often inserted with the trapezius, and fre- 
quently passes backwards crossed by the cephalo-humeral muscle, to be 
inserted into the acromion close to or beneath the acromial part of the 
trapezius.¢t+ It is double in Cercoleptes.$$ 
p Pves.$$ 
M. sternomastoideus (figs 2, 3, and 5 s.m.) takes origin from 
the anterior projection of the presternal rostrum, and forms a 
rounded orprismatic fleshy mass inserted into the mastoid region 
of the skull just above the external auditory meatus and under 
cover of the parotid gland. 
The fibrous continuation of the imperfect clavicle passes in- 
wards to the presternal rostrum just dorsad of the origin of the 
muscle. The muscles of opposite sides are in partial contact close 
to their origins. 
No cleido-mastoid element is present, though such is present in 
all other marsupials; and, as already mentioned,|||| the cleido- 
occipital, common to all other marsupials, is likewise absent 
unless the fibres I have named cleido-trapezius are to be regarded 
as such. 
= xi... page 212.) viz Pl jJo,0e, band El.."i7,ns..2. (xl, pagesdgs: 
Faaevies pace 728%, || vis Bly 252) solves Bh 245. ** Ct, alsoviceel, 
940 and 249. ‘ttix., page 180.. tf vi. Pl., page 109. §§1., page 547. 
\||| Supra. 
