64 BRITISH TUNIOATA. 



(PL XXVII, figs. 6 and 7) is composed of several 

 laminated lobules, five or six on one side and one or 

 two 011 the other ; the laminae are sharply defined and 

 the lobules more or less rounded. The border of the 

 anal orifice is smooth and turned back. 



The reproductive organs (PI. XXVII, figs. 6 and 7, 

 PI. XXVIII, figs, o and 5, and fig. 4(3 in text) are large, 

 wide, and somewhat irregularly-formed masses occupy- 

 ing the usual positions, one on each side of the body ; 

 the form of the right-hand organ inclines to oval, and 

 lies against the rectal portion of the intestine, in front 

 and above the loop. The male organ (fig. 47), which 

 is composed of comparatively large, isolated, ovate 

 casca arranged in pairs, fringes the upper margin of 



FIG. 47. Male testicles of Molgula citrina. More highly magnified. 



the ovarian mass ; at the lower margin near the origin 

 of the oviducts there is another patch of male caeca. 

 The left-hand genital mass is subtriangular with the 



^ . 



upper and posterior slope bordered by a similar fringe 

 of male caeca, and at the lower side, towards the 

 oviduct, there is also a similar belt of these caeca. The 

 oviducts are long, narrow tubes, which, turning 

 abruptly up in front of the organ, incline towards the 

 atrium ; they are accompanied by the vas deferens, 

 both conduits terminating at the same point ; but what 

 is peculiar is that one of the tubes, apparently the 

 oviduct, is entire only for a short distance, and then 

 becomes an open deep groove, and so continues to the 

 termination. 



The cylindrical organ in connection with the heart is 



