164 MR. A. SANDERS ON LIOLEPIS BELLI. [Feb. 6, 



Quadratus lumborum arises from the anterior edge of the sacrum ; 

 by its ventral surface it is attached to all the six lumbar ribs ; its 

 insertion is into the posterior surface of the last dorsal rib. 



Pectoralis major (fog. 1 ) arises from the posterior border of the inner 

 end of the clavicle, from the interclavicle, and from the central line of 

 the whole length of the sternum, also from the postero-lateral border 

 of the same, and from the concave edge of the extremely long xiphi- 

 sternum, as far as its extremity : the anterior fibres go backwards 

 and outwards, the middle go directly outwards, and the posterior 

 directly forwards ; all converge and are inserted into the inner border 

 of the tuberosity of the humerus. 



Deltoid (figs. 1, 2, & 3) arises from the anterior surface of the 

 clavicle for rather more than half its extent, and, passing in front, it 

 emerges posteriorly round its dorsal border, receiving a reinforcement 

 of fibres from its posterior surface ; it is inserted into the external 

 border of the humerus just beyond the tuberosity. This appears to 

 represent the clavicular portion of the deltoid ; and in this specimen 

 I think that the scapular portion is wanting. 



Supraspinatus (figs. 1 & 3) arises from the greater portion of the 

 outer surface of the coracoid, occupying the bone bordering the 

 coracoid fenestra anteriorly, and the tongue of bone between it and 

 the eoraco- scapular fenestra; it also covers the coracoid half of the 

 latter ; it is covered by the deltoid and is inserted into the summit 

 or anterior point of the tuberosity of the humerus ; a few fibres are 

 inserted into the head of the bone itself and into the capsular 

 ligament. 



Teres minor (fig. 3) arises from about half the coraco-scapular 

 fenestra, and from the surface of the scapula in front and dorsad of 

 the same ; near its insertion it is bound down by an aponeurosis, 

 connecting the long head of the triceps with the head of the humerus ; 

 it then passes beneath the outer head of the same muscle to be in- 

 serted into the inner edge of the dorsal surface of the humerus a very 

 short distance beyond its head. 



Infraspinatus (figs. 2 & 3) arises by a somewhat semicircular origin 

 from the outer surface of the suprascapula, commencing anteriorly 

 from the point of articulation with the clavicle, and extending nearly 

 to the postero-dorsal angle, leaving a space at the antero-dorsal angle 

 for the levator ; from this origin the fibres converge and are inserted 

 by a thin flat tendon into the outside of the humerus, immediately 

 beyond the insertion of the supraspinatus, between it and the insertion 

 of the deltoid. The muscle which in the Frog arises from the supra- 

 scapula was considered by Duges* to correspond to the " sous-epi- 

 neux et grand rond." 



In detailing the myology of Gecko, I ventured to name these 

 three muscles thus on account of their insertions resembling in 

 their arrangement the corresponding insertions in anthropotomy — 

 the supraspinatus occupying the summit of the great tuberosity of 

 the humerus, the infraspinatus the middle, and the teres minor the 

 lower of the three depressions on that apophysis. This arrangement 



* ' Eecherches sur l'ost^ologic et la myologie des Batraeiens,' Paris, 1835. 



