424 Proceedings of the Royal Irish Academy. 



inserted by two slips into trapezium and base of second metacarpal 

 bone {radio-cavpo-metacarpcdis). 



Falmaris longus. — This, which, enjoys the distinction of being the 

 most variable muscle in the body, I found absent in four of thirty -four 

 subjects. In one case the deficiency was symmetrical ; in the other 

 three unilateral — two on the left side, one on the right. In the case 

 of bilateral absence, the subject was a female, the others were males. 

 A second head from the coronoid process was present in two instances. 

 There was one example in which the fleshy belly was two and a-half 

 inches in length. In one case the tendon was inserted directly into 

 the outer margin of the abductor poUicis, just below its origin. 



I have since met with a specimen in which the insertion was into 

 the tuberosity of the scaphoid bone. Also an example of doubling of the 

 muscle, both heads coming from the internal condyle, but the second 

 head lying beneath the other, and not coming from the common tendon. 

 The deep head has received the name of 'pcdmaris longus accessorius 

 (Krause). 



Flexor digitorum sidtlimis. — Absence of the tendon for the little 

 finger I have observed in three instances. The index flexor I have, 

 in two cases, found quite distinct from the rest of the muscle, from 

 its origin to its insertion. 



Flexor carfi idnaris. — This muscle I have once found wholly inserted 

 into the anterior annular ligament. The palmaris longus was absent. 

 Flexor carpi idnaris hrevis. — Of this muscle I have met with one 

 specimen. The origin was from the ulna, inside the upper end of the 

 flexor digitorum sublimis, for about two inches in length. It passed 

 through a separate canal in the anterior annular ligament, and was 

 inserted into the base of the fourth metacarpal bone. 



Flexor digitorum profundus. — The only notable variety of this 

 muscle I have seen was a complete isolation of the index portion along 

 its whole length. This occurred twice in thirty-four subjects exa- 

 mined; and I have seen some other examples, of which I took no note. 

 Flexor digitorum proficndus accessorius ; muscidus accessorius ad digi- 

 torum profundum (Grantzner). — One example of this muscle I have 

 seen arising from the inner side of the coronoid process; it formed two 

 tendons which went to the middle and little fingers. The tendons 

 pierced the corresponding ones of the sublimis, and were accompanied 

 by very small tendinous bands from the normal fiexor profundus. 



Flexor pollicis longus. — This muscle received, in two cases of the 

 thirty -four subjects specially examined, an accessory head from the 

 internal condyle. The coronoid head, which in some form was pre- 

 sent in eighteen cases, arose separately in nine ; in common with the 

 deep head of pronator radii teres, in three ; closely adherent to the coro- 

 noid head of flexor sublimis digitorum, in four; and by a slip common 

 to all three in the remaining two. An accessory slip, coming directly 

 from the fleshy fibres of the flexor sublimis digitorum, was present in 

 one case ; and such a muscular bundle is mentioned by Krause under 

 the name oi fascicidiis exilis. 



Pronator radii quadratus. — Complete separation into two parts 



