134 



have found, or has been described by others, as involving the following 

 muscles : — 



Tensor tarsi. 



Obliquus superior oculi (Albinus). 

 Corrugator supercilii. 

 Zygomaticus minor (Morgagni et mihi). 

 Digastric (Albinus). 



Digastric anterior belly and single poste- 

 rior. 



Styloglossus (Meckel). 



Sbylopharyngeus (Bohraer). 



Sternothyroid (Gantzer et mihi). 



Thyro-hyoid (Cowper). 



Levator anguli scapulae. 



Supinator longus. 



Palmaris longus. 



Extensor ossis metacarpi pollicis. 



Extensor secundi internodii pollicis. 



Extensor minimi digiti. 



Subclavius, 



Scalenus posticus. 



Supinator brevis (Fleischmann, Sandiforf, 



et mihi). 

 Genio-hycid (M'Whimne). 

 Sartorius (Rosenmiiller). 

 Scalenus anticus. 

 Abductor pollicis brevis. 

 Extensor indicis. 

 Rectus thoracicus. 



Popliteus (Fabricius ab Aquapendente, 



Bevan et mihi). 

 Cremaster (Cowper). 

 Adductor longus. 

 Rectus capitis lateralis. 

 Rectus capitis posticus major. 

 Pyramidalis. 

 Pyiiformis. 



The second form of duplication, or that of superimposed strata, has 

 occurred in the cases of the following : — 



Pectoralis major. 

 Pectoralis minor.- 

 Trapezius (Tiedeinann). 

 Rhomboids. 



Pronator quadratus (M'Whinnie et mihi). 



Complexus. 



Glutseus maximus. 



Adductor magnus. 

 Vastus externus. 

 Vastus internus. 

 Gastrocnemius. 

 Solseus. 



External oblique (Tiedemann). I have 

 seen instances of this confined to the left 

 side. 



The occurrence of this class of anomaly can only be accounted for 

 on the principle of vegetative repetition of parts — a principle upon 

 which we explain those abnormal instances of supernumerary limbs or 

 members, and even complete janiceps. The vital capacity for exertion 

 conferred by anomalies of this class is not easily ascertained ; but most 

 probably the existence of multiple irregularities of this nature would 

 be co-existent with, and causative of, increased power, as in the cele- 

 brated case given by Tiedemann. The most common seat of laminar 

 reduplication I believe to be the rhomboides ; of parallel multiplicity, 

 the short extensors of the thumb. 



Variations of the third class, or those by fission, have occurred in the 

 cases of many muscles: — (1) the great pectoral, which in one sub- 

 ject was widely differentiated, no fibres arising from the manubrium 

 sterni ; (2) in the sternomastoid fission has occurred in several in- 

 stances, similar to No. 3, in my former paper ; (3) fissions of the biceps ; 

 (4) coracobrachial ; (5) gluteus maximus ; (6) quadratus femoris ; 

 (7) flexor sublimis digitorum ; (8) subscapularis ; (9) adductor mag- 

 nus; (10) adductor longus; (11) brachialis anticus; and, (12) flexor 

 brevis pollicis have occurred, similar to that already described ; and to 



