Knott — On Abnormalities in Human Myology. 419 



rare muscle arises from the front of the manubrium sterni and cartilage 

 of first rib, and passes outward between pectoralis major and minor, to 

 be inserted into the front of the capsule of the shoulder- joint. I have 

 found on one occasion a bundle of fibres arising from the cartilage of 

 the first rib at its junction with the bone, and passing outwards between 

 the greater and lesser pectoral muscles, to be inserted into the anterior 

 aspect of the shoiilder capsule. 



To the anomalies of the muscles of the back, of the diaphragm, and 

 of the flat muscles of the abdomen I have not given special attention, 

 although some remarkable deviations from the typical arrangement 

 have been met with. 



Basio-deltoicleus ; fasciculus infraspinata deltoideus (Gruber). — This 

 bundle of fibres is accessory to the normal deltoid muscle, and corre- 

 sponds to the abductor brachii inferior of the lower mammals ("W. 

 Krause, Anatomic des Kaninchens, 1868). It arises from the vertebral 

 border of the scapula at a variable level, sometimes as low down as the 

 inferior angle of the bone, and passes outwards to join the lower fibres 

 of the deltoid. Of this form of the accessory muscle I have met with 

 two examples. Other accessory bundles have been described. One 

 from the axillary border of the scapula has been named costo-deltoideus: 

 a separate slip from the acromial end of the clavicle has been named 

 acromio-clavicularis lateralis. Still rarer specimens are those which 

 have been described under the names of tensor fasciae deltoideac a fascia 

 infraspinata and tensor fasciae deltoideac a margine axillari scapulae, 

 respectively. I have never met with any of these latter forms. 



Infraspinatus. — This muscle I have twice seen to receive an acces- 

 sory slip from the deltoid. I have seen a good many specimens (over 

 five in number) in which it was quite inseparable from the teres minor. 

 The upper fibres of the muscle are sometimes quite separate from the 

 remainder, forming what has been described as the infraspinatus mi- 

 nor. Of this variety I have seen one well-defined example. 



Teres minor. — Fusion with the infra-spinatus has been already 

 mentioned. Complete absence of the muscle I have once observed. 



Teres minimus. — Under this name has been described a bundle of 

 fibres parallel to and in close contact with the lower edge of the teres 

 minor. I have seen one example occurring on both sides of a male 

 subject of great muscular development. 



Subscapularis minor; suiglenoidalis ; infraspinatus secundus; suh- 

 scapulo-hicmeralis ; subscapulo-capsularis. — tinder this name has been 

 described an upper detached portion of the subscapularis muscle. 

 Arising from the upper part of the axillary border of the scapula, 

 sometimes from the tuberculum infra-glenoidale, where it adheres to 

 the long head of the triceps, it passes outwards to be inserted either 

 with the normal subscapular tendon into the lesser tuberosity of the 

 humerus, or what much more frequently happens, into the front of the 

 capsule of the shoulder- joint {suhscapulo-capsularis, Gruber, Macalis- 

 ter). According to Professor "VV. Krause, the frequency of its occur- 

 rence varies from five to thirty-three per cent. I have found it four 



K. I. A. PROC, SER. II. VOL. III. — SCIENCE. 2 N 



