472 DR. R. W. SHUFELDT ON [Nov. 16, 
discovered during his dissections of the arms of birds ; this was the 
presence or absence of the expansor secundariorum muscle (Coll. 
Sci. Papers, p. 323). As this delicate muscle and its tendon is 
well developed in the Storks, he, for convenience sake, termed it 
the Ciconine character. He found the Cuculidze to be Ciconine 
birds so far as this structure was concerned, but I find after a very 
careful search in both pectoral limbs of my specimen of Geococcyx 
that this character is missing in it. This, then, constitutes another 
difference between Geococcyx and the Cuculide. 
Of the Pectoral Muscles. 
All three of the pectoral muscles are present in this bird, and all 
conspicuously developed, although the pectoralis tertius is consider- 
ably larger in comparison than is usually the case. Their muscular 
fibres are remarkable for their fine texture and compactness, both of 
which qualities, added to their pale colour, lend to these structures 
a very delicate appearance. 
Nothing of a peculiar nature seems to distinguish either the 
pectoralis major or secundus, as they both arise and are inserted ina 
manner common to the majority of the class. 
On the other hand, the pectoralis tertius, although inserted as 
we usually find it in birds, has no sternal origin, but arises from the 
externo-anterior aspect of the sternal extremity of the coracoid, as 
well as from the side of the shaft of the same bone. 
Recent dissections of mine, performed upon various species of the 
Corvidee, go to show that in them this muscle has quite an extensive 
origin upon the sternum, and its bulk sinks into insignificance when 
compared with the size of the great pectoral as it exists in all of the 
species of this latter group which I have examined. 
On the Myology of the Pelvic Limb in Geococcyx. 
Quite recently I have completed a very extensive chapter on the 
muscles of birds, and the MS. of this piece of work, with the 
nearly one hundred woodcuts that illustrate it, are at hand at the 
present writing. So with the bird now before us I will, without 
further explanation, adopt the myological nomenclature which I 
have proposed in my MS., without discussion of such points as 
wherein I may differ in homologies or terms with other authorities. 
Such differences, and I trust they may be few and well sustained, 
must be left for decision until such time as the work referred to 
appears in type. 
It is my aim here to enter quite extensively into the description of 
the muscles of the pelvic limb of Geococeyx, as they offer us many 
points of interest. 
We find the sartorius muscle (Plate XLIV. fig. 1, 8) powerfully 
developed in Geococcyx, as are the majority of the muscles of the 
thigh in this bird. It arises, semitendinous, from the crest of the 
neural spine of the last vertebra of the dorsal region of the spine, from 
the summit of the anterior portion of the crista of the sacrum, and from 
the adjacent surface of the superior aspect of the ilium on the cor- 
