Parker and Ricu—Ox the Myology of Palinurus Edwardsi, Ffutton. 171 
The short adductor of the tail fin arises from the outer corner of the anterior 
edge of the tergum of the telson, and is inserted into the ventral edge of the basi- 
podite of the lateral tail-lobe immediately caudad of the flexor tendon. 
The external abductor of the exopodite arises from the anterior face of the 
basipodite, and is inserted into the outer corner of the proximal edge of the 
exopodite. 
The Jong abductor of the exopodite arises from the dorsal region of the proximal 
border of the basipodite, and has an extensive insertion into the dorsal plate of the 
exopodite. 
The zxternal abductor of the exopodite arises from the ventral surface of the 
basipodite, and is inserted into the dorsal surface of the proximal border of the 
exopodite. 
The ventral adductor of the exopodite arises from the ventral surface of the 
basipodite towards its mesial side, and passes obliquely upwards and outwards to its 
insertion in the dorsal plate of the exopodite near its proximal end. 
The long adductor of the exopodite arises from the middle of the dorsal surface of 
the basipodite, and has an extensive insertion into the dorsal plate of the exopodite. 
The short adductor of the exopodite arises from the dorsal surface of the basi- 
podite, and is inserted into the ventral region of the proximal edge of the exopodite. 
The adductor of the endopodite arises from the middle of the dorsal surface of the 
basipodite and has a long insertion into the dorsal plate of the endopodite. 
4. Extrinsic muscles of the second maxilla (fig. 20). 
The extrinsic muscles of the second maxilla are of great size, considering the 
dimensions of the appendage itself: they act upon the scaphognathite and are 
therefore to be looked upon as the chief respiratory muscles. 
The protractors, or muscles which draw the scaphognathite forwards and inwards, 
are two long parallel-sided bands arising from the cephalic apodeme and inserted into 
the basal region of the appendages. They are opposed by a dong retractor which 
arises from the maxillary sternum, and by a fan-shaped, two-headed, short retractor 
which arises at the junction of the maxillary sternum with the cephalic apodeme. 
5. Eatrinsic muscles of the first maxilla (fig. 19). 
The peculiar sifting movements of the first maxilla are performed by four 
adductor slips arising from the cephalic apodeme, and by a very distinct abductor, in 
