| OCR Text |
Show 472 DR. R. W. SHUFELDT ON [Nov. 16, discovered during his dissections of the arms of birds ; this was 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 Cuculidae 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 Cuculidae. Of the Pectoral Muscles. All three of the pectoral muscles are present in this bird, and all conspicuously developed, although the pectoralis tertius is considerably 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 in a 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 Corvidae, 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 Myoloyy 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 tbe 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 Geococcyx, as they offer us many points of interest. W e find the sartorius muscle (Plate XLIV. fig. 1, S) 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- |
