422 Proceedings of the Royal Irish Academy. 



(Struthers). — This slip arises from the inner side of the biceps, and 

 passing obliquely downwards and inwards, crosses in front of the 

 brachial artery, and is inserted into the fascia over the pronator radii 

 teres. Of this anomaly I have met with fonr examples. 



Bracliialis anticus. — This mnscle I have found in three instances 

 completely cleft from origin to insertion — but its attachments 

 were in other respects quite normal. Continuity of its outer fibres 

 with those of the supinator longus, as described by Wood and Macalis- 

 ter, I have seen in one case, giving rise to the formation of a tunnel 

 through which passed the musculo-spiral nerve with the accompanying 

 branch of the superior profunda artery. An accessory head from coraco- 

 brachialis I have seen in two instances. Of its inferior attachments I 

 have seen the following varieties: — sending a slip to the tendon of the 

 pronator radii teres — this I have observed twice ; a slip to the supinator 

 longus below the level of the elbow joint — this I have seen occurring 

 on both sides in one subject ; a slip to the flexor sublimis digitorum — 

 of which I found one example in a very muscular subject (male). 



Bracliialis interyius minor. — Of this muscle, which is but a detached 

 slip of the brachialis anticus, I have met with three specimens in forty- 

 nine subjects. In two cases it lay on the radial side of the muscle, 

 and was inserted into the radius at the inferior part of the bicipital 

 tuberosity ; in one it lay on the inner side of the muscle, and was in- 

 serted separately a little below the level of coronoid process. 



Triceps Irachii. — I have seen few noteworthy variations from the 

 typical attachments of this muscle. Apparent direct continuity of the 

 triceps and anconeus I have several times observed. A distinct slip 

 from the tendon of the subscapularis at its attachment of the lesser 

 tuberosity I have once seen. In two cases of seventeen subjects 

 (which were specially examined for it) I found a bursa between the 

 internal part of the triceps and the ulnar nerve as it lies behind the 

 epitrochlea. {Bursa mucosa retro-ejntrochlearis of Gruber.) I have 

 noted four examples of the accessory slip from the lower border of the 

 tendon of the latissimus dorsi, described by Professor Halbertsma under 

 the name of anco7ieus quintus. 



Another muscular slip has been described under the name of anconeus 

 quintus (vel minimus) ; epitroclileo-anconeus (of Gruber) ; anconeus epi- 

 trocldearis (Wood). — This muscle arises from the back of the inner 

 condyle of the humerus, and is inserted into the olecranon process of 

 the ulna. Its bulk and extent of attachment are very various ; ac- 

 cording to most authorities it would seem to be present in about 

 a fourth of the subjects examined. 



Suianconeus. — The only peculiarity I have met with in this muscle 

 is the frequency of its absence. Indeed I have but seldom been able 

 to define its existence as a separate muscle, and have been led to won- 

 der why it is described in all the hand-books as a separate muscle. 

 "Under the head of the anomalies of the triceps extensor cubiti, I 

 would also include the slip described by Gruber under the name of the 

 levator tendinis latissimi dorsi. It arises from the coraeoid process and 



