'.34 MR. J. C. GALTON ON DASYPUS SEXCINCTUS. 



that Prof. Rolleston proposed for it the distinctive term " pyramidal " portion — a name 

 derived from the muscle subjacent to the aponeurosis with which it was continuous. 



Reptiles and Batrachians, as well as Mammals, are able to furnish instances of the 

 modification of the pectoralis major mentioned above. 



I have found a like downward continuation of the pectoralis into the aponeurosis 

 covering the rectus abdominis in a young Crocodile ; and Ecker, in his Monograph upon 

 the .Frog, describes and figures under the name " portio abdominalis " (abdomino-humeral, 

 Bilges) a similar prolongation of this muscle, " welche mit der Aponeurose des M. obli- 

 i//'us abdominis externus in Verbindung steht "\ 



Pectoralis minor.— 1 did not succeed in finding any representative of this muscle. 



According to Meckel, this muscle is absent in Myrmecophaga and Bradypus amon 



among Marsupials, in the Opossum and Kangaroo, and in most Rodents 



Edent 





Further on, he describes in Dasypus a muscle which passes from the first rib, under the 

 pectoralis major, to the humerus, where it finds insertion above this latter muscle. A 

 similar muscle is present in Arctomys, but arises from the middle region of the sternum. 

 Meckel suggests that this muscle may not be the pectoralis minor after all, but a 

 differentiated portion of the great pectoral \ May it not be, however, the subclavius ? 



Coraco-brachialis.-^Thk muscle arises from the coracoid process of the scapula by a 

 strong and fair-sized tendon. About the distance of half an inch from its origin, 

 where muscular fibres begin to blend with the tendon, a delicate slip is given off from 

 t lie inner side of the muscle, which winds round beneath the inner tuberosity of the 

 humerus, to be inserted into the neck of the bone, or capsule of the joint, at a point 

 between the articular head and the above tuberosity. This muscular offset evidently 

 represents the « short » variety, as it has been termed by Mr. John Wood. At the 

 distance of an inch after giving off the above muscular slip, the coraco-brachialis joins 

 tue biceps, and is partly continued with this muscle into the forearm, partly is prolonged, 

 as a considerable slip, to the ridge which runs upward from the inner condyle to form 

 he anterior boundary of the supracondyloid foramen. This, the « long » varie^ . 

 the mnsele is the only form recorded by Mr. Wood 3 as being present in the Armadillo 



which however, the species examined is not mentioned. The "short" varies . 



muscle was present, in a condition of equal development, on both sides in the Oxfoi 



ty 



ty of 



B pecimen of Dasyi 



which I examined, and on the left side (the only 



of Sur 



I 1 1 li%?°H } ° f the S1,eCimeU bel0H § in S t0 the %d College O! surgeon 



we J ir, t ., that a feW fibreS ° f the terminal P° rti ™ of t^ " l°"g " ™ riet y 



-e hi Jt r teri01 ' b ° Undary ° f the ™W°* ^ameu, and at a higher 



1 Die Anatomie des Frosches V™ tw a i i -^ ^ 



8 Op. A pp. 490-91. ndCT EckCr ( Braunsc ^eig, 1864). Iste Abtheil. p. 95, fig. 73. 



™en just ab™e\he^L ( rwnir tb "^^ " ^ *** "^ ** im P lanted u P on the ^pracondyloid arch or 

 tions and their Ration to tW ' I !" J"** 131 * tbe lon S varie tJ of the muscle."— On Human Muscular Varia- 

 << abridge, 1867) vol i p 51 * ^^ B * J ° hn Wood > F.R.C.S.-Journ. of Anat. and Phys. 1st scr. 



