Knott— 0^^ Muscular Anomalies. 635 



sory slip of origin from the lumbar aponeurosis occurred in two of 

 these. This I have also noticed in three other instances. 



Gluteus medius. — In five cases the anterior edge of this muscle 

 adhered intimately to that of the minimus. A bond of union between 

 the anterior edge and that of the gluteus minimus, with the fascia 

 lata, is formed by the ligamentum suspensorium ossis femoris of 

 Gunther (ligamentum suspensorium trochanteris of Henle). When 

 well developed, this band is about seven centimetres in breadth, and 

 reaches from the outer lip of the iliac crest to a little below the 

 trochanter major. 



Gluteus yninimus. — This muscle I have twice seen pierced by the 

 gluteal vessels and superior gluteal nerve. In one of these the 

 inferior segment was adherent to the pyriformis for the greater part of 

 its length. 



Gluteus accessorius. — A deep inner lamina of gluteus minimus 

 passing with the tendon of the latter to its insertion, and separated 

 from it by a thin layer of areolar tissue. Three specimens noted. 



Gluteus quartus ; scansorius ; invertor femoris. — This name has been 

 given to a differentiated anterior segment of the gluteus minimus, 

 which stretches forwards and upwards to the anterior superior spine. 

 The specimens of this anomalous muscle which I had noted were 

 placed on record last year. It was met with once last winter, in 

 which case the occurrence was symmetrical, the insertion being on 

 one side into the trochanter major with that of gluteus minimus, and 

 on the other partly into the trochanter, and partly to the side of the 

 vastus externus. 



Pyriformis. — This muscle varies a good deal in the degree of its 

 development, but I have never met with a ease of complete absence, 

 such as has been described by Budge and by Macalister. I have noted 

 two instances in which the sacral digitations were reduced to two. 

 Both had been the subjects (on the corresponding side) of chronic 

 rheumatic arthritis. The iliac origin (at upper border of great sacro- 

 sciatic notch) was twice in forty cases separated by a distinct 

 areolar layer from the sacral portion of the muscle. The superior 

 gluteal nerve perforated the upper part of the muscle in one case. The 

 splitting by the great sciatic nerve occurred three times in forty lower 

 limbs ; once it was bilateral. 



Gemellus superior. — This muscle I have found absent in a consider- 

 able number of instances. Once I found its fibres joining the tendon 

 of pyriformis, instead of that of obturator internus. In three cases 

 dissected by me the muscle could easily be separated into two parts. 



Gemellus inferior. — During the last winter session I noted for 

 the first time two instances of the absence of this muscle. I have 

 several times found the muscle easily divisible into two or even three 

 fasciculi. Two cases have also been noted in which connecting fasci- 

 culi passed from this muscle to the adjacent margin of the quadratus 

 femoris. 



Obturator internus. — Slight variations in the field of origin of this 



R. I. A. i'KOC, SER. II., VOL. III.— SCIENCE. 3 L 



