'3° 



ELA SMOBRA NCHII 



fold is produced at its hinder margin into an outstanding lobe. The 

 basi pterygium is continued backwards into this lobe as a cartilage 

 rod, consisting, as a rule, of two short anterior and one long 

 posterior segment. A dorsal groove carrying the skin with it is 



Fig. 89. 



Raja Manila, Holt. Dorsal view; the cartilaginous skeleton lias been completely 

 on the right side, a, b, c, d, /, cartilages of clasper ; a. I, anterior lobe of pelvic fin; bp, 

 basi pterygium ; cl, clasper ; e.p, covering-plate ; i.p, iliac process ; o.s, opening of sac ; p, pelvic 

 girdle; p.p, prepubic process; pr.r, enlarged preaxial radial; pt, posterior preaxial radial : s, 

 dotted line indicating ventral glandular sac; st, second segment of basipterygial a\-s ; ■'>,. 

 styliform cartilage. 



developed along this terminal piece, which becomes hollowed out to 

 receive it. The edges of the cartilage are rolled round so as almost 

 completely to enclose the. groove in a split tube open at both ends 

 (Fig. 88). Spermatozoa may pass in at the front and out at the 

 hind end. The internal tegumentary tube projects forward as a 

 blind sac, and from its wall develops a special gland. The main 



