58 BRITISH TUNICATA. 



figs. 1 and 2, and fig. 44 in text) displays, in distinct 

 much-curved lines, the rows of the pouch-orifices, 

 which are of a squarish form; the folds are rather 

 wide and deeply arched, the lower extremities being- 

 turned well forward towards the oral orifice; the 

 ventral margin is much contracted, consequently the 

 anterior folds are short, as well as the oral lamina, 

 which is extremely narrow. Between the folds the 

 secondary vessels are very irregular and are only 

 approximately convoluted, the stomata being short and 

 variously contorted. Within the folds there are obscure 



. 



indications of spirals, arranged as usual in pairs ; the 

 folds bear three or four wide, membranous rods on 

 each side. The branchial tubercle (PL XL VIII, fig. 2) 

 is well developed. There are twelve or fourteen very 

 large, tripinnate, tentacular filaments, which are pretty 

 equal in size, and form a bushy fringe at the base of 

 the tube. 



The intestinal loops, of which there are two, are 

 placed diagonally upwards and forwards, the upper 

 loop not quite reaching across the mantle ; the anal 

 orifice has a narrow, smooth, reflected rim. 



The genital organs (PI. XXVIII, figs. 1 and 2) are 

 rather long and narrow, and somewhat curved ; the 

 right-hand ovary fills up the space within the lower 

 loop, and the left-hand one is placed a little above the 

 cardiac cylinder ; they are each composed of an in- 

 distinct double longitudinal series of irregular ovarian 

 lobules. The male organ appears to be made up of 

 two or three irregularly-rounded bodies placed towards 

 the front of the mass. The ducts of the two elements 

 are placed one over the other, and so closely united as 

 to appear as a single delicate constricted tube ; they 

 terminate a little in front of the organ in two nipple- 

 like orifices. 



The cardiac cylinder is situated a little below the 

 genital organ, and is short, almost straight, with the 

 extremities obtuse. 



