M. V. Lebour 
439 
Ge^'caria huccini sp. inq. 
(PI. XXVII, figs. 17, 18.) 
This is the largest of the three cercariae belonging to this group. 
It occurs in Buccinum undatum brought in by the fishing boats, four 
out of 80 examined. It is contained in long and almost colourless 
sporocysts which occupy the digestive gland in enormous numbers. 
The gonad is not destroyed by tins Trematode as is very usually the 
case with others. 
The sporocysts measure 1'4 mm. to 3 mm. in length, pale yellow 
or colourless and sausage-shaped. They may be 20-30 cercariae in 
each sporocyst. 
The cercaria measures 0'33 mm. including its tail, tail 0'06 mm., 
oral sucker 0'045 mm. across, armed with a stylet with four points 
anteriorly, the middle pair long and the outer short, bluntly rounded 
behind. The ventral sucker is situated well behind the centre of the 
body and is almost exactly the same size as the oral sucker. Between 
the two suckers are the stylet glands with six ducts, three on each side 
opening by the sides of the stylet anteriorly and dorsally. Behind the 
ventral sucker is a large excretory vesicle lined with very large cells. 
Further life-history unknown. 
(e) Lepodora group)- 
Genus Lepodora. 
Lepodoi'a rachiaea (Cobb.) ? (Lebour, 1907 B, p. 102, and 1908 B, p. 20). 
(PI. XXVII, figs. 19, 20.) 
The cercaria which is probably the larval stage of Lepodora rachiaea 
is very difficult to place in relation to any other larval forms. I have 
therefore left it at the bottom of the group developed in sporocysts. 
It inhabits Gardium edide and is contained within sporocysts where 
it encysts. It was found twice by myself in cockles from Budle and 
Holy Island and once by Johnstone from Morecombe Bay completely 
riddling the visceral mass of the host. 
The sporocysts are sausage-shaped and quite colourless. Sometimes 
they are active and constantly changing their shape, at other times 
they are quite inert. They measure about 0’60 mm. long and 0‘15 mm. 
broad. Inside are cercariae in all stages, the older examples encysted 
