10 
In the Cat the three sectors correspond to the cleido- acromio- and 
spino trapezius of Notoryctes (i.e., the clavo-acromio- and dorso- 
cucullaris of Strauss-Durckheim). The fibres I have named “ delto- 
trapezius” are simply “cephalo-humeral” fibres belonging to the 
claricular system of trapezius fibres. 
I am doubtful whether the segment described above as cleido- 
trapezius is or is not to be regarded as the equivalent of a cleido- 
occipital. A muscle corresponding to the latter is otherwise absent, but 
a cleido-trapezius very like that in Notoryctes occasionally co-exists 
with a true cleido-occipital, e.g., in Koala,* Cuscus,+ Phalangista 
vulpina,t amongst other marsupials.$ The origin of the trapezius sheet 
in this order varies chiefly in the number of dorsal spines which give 
it origin, e.g., from all in Dasyurus, or only from seven in Thylacinus, 
Phascogale and Cuscus, and nine or ten in Sarcophilus. It arises from 
the occipital crest, and ligamentum nuche also in most. Its insertion 
is in all marsupials mainly into the spine or spine and acromion, but 
the anterior fibres have a variable insertion, and often wholly 
(Dasywrus) or partly (Phalangista) form a cephalo-humeral bundle 
passing, to be inserted along with deltoid, like the delto-trapezius 
in Notoryctes. 
In Wombat this anterior part passes over the clavicle and replace 
the clavicular part of deltoid, while again in Sarcophilus no part of the 
muscle reaches the humerus, the anterior fibres being inserted into the 
outer fourth of the clavicle.|| 
Macalister’s view (adopted by MacCormick for Dasywrus and 
Phalangista) that the humeral fibres of the trapezius in Phascolomys 
correspond to those of the “ cephalo humeral” muscle found in other 
orders is opposed by Lechefl, but, as it appears to me, on quite insuf- 
ficient grounds. His argument that in Dasywrus and Myrmecobius there 
is a “pars clavicularis deltoidei’’ independently of the humeral 
trapezius is sufficiently answered by reference to the conditions in 
Phalangista** and Phascolomys, where a part or the whole respectively 
of the clavicular deltoid is replaced by what are plainly fibres corre- 
sponding to the humeral fibres of the trapezius in Dasywrus. One need 
only suppose that the pars clavicularis deltoidei in the latter animal, 
which is concealed by the humeral slip of the trapezius, answers only 
to the deeper part of the whole clavicular deltoid. 
No corresponding segmentation of the anterior part of the trapezius 
is present in Monotremes. 
In Echidnatt the muscle is inserted into part of the dorsal 
border of the scapula, along the scapular spine, by means of a fibrous 
arch, and to the acromion and outer part of clavicle. In Ornithorhyn- 
chus it is inserted into the dorsal scapular margin and the clavicle and 
inter-clavicle. 
Macalister,{{ after describing a cleido-occipital in Chlamydophorus, 
and stating that “in no other Edentate does this muscle seem to exist 
distinctly,’ goes on to say, “ Professor Hyrtl describes a third muscle 
external to the cleido-mastoid, but much stronger, which ascends with 
it, and is inserted into the lambdoid suture, and into the temporal 
*Ixxii., page 222. tiv., page 4. {xxxvi., page 104. §vi. Plate, 
174 a+, and Plate 176, fig. 1., a+. || xxix., page 154. {[ xxvi., page 719. 
** xxxvi., fig. 7 é., and vi. Pl., 177. tt lxii., page 12. 4 xxvii., page 238. 
