M. V. Lebour 
455 
Figs. 3-12. Spelotrerna excellens Nicoll. 
3. Sporocyst (length 0'6 mm.). 
4. Tailed cercaria { = Cercaria ubiquita) (length 0-12 mm.). ^ 
5-6. The cercaria having just entered Carcinus maenas and covered itself 
with a very thin cyst (O'Old mm. across). 
7-11. Are various stages in the encystmeut of the cercaria drawn in 
proportion. 
12. The cercaria pressed out of the cyst (length 0'8 mm.). 
Figs. 13, 14. Cercaria carcini Lebour. 
13. Cercaria bursting out of cyst (length of cyst 0-4 mm.). 
14. Cercaria pressed out of cyst (length 0'54 mm.). 
Figs. 1-5-17. Cercaria balani Lebour. 
15. Encysted cercaria (cyst 0-4 mm.). 
16. Cercaria pressed out of cyst (length 1 mm.). 
17. Small cyst from Balaims halanoides (0T5 mm.). 
Figs. 18, 19. Cercaria corophii Lebour. 
18. Encysted cercaria (length of cyst 0'16 mm.). ^ 
19. Cercaria pressed out of cyst (length 0-34 mm.). 
PLATE XXVII. 
Figs. 1, 2. Cercaria minor sp. inq. 
1. Encysted cercaria (cyst 0’26 mm.). 
2. Cercaria pressed out of cyst (length 0‘52 mm.). 
Figs. 3-7. Cercaria littorinae-rudis sp. inq. 
3. Sporocysts (1 mm. across). 
4. Cercaria pressed out of cyst (length 0-25 mm.). 
5-7. Different aspects of cercariae within sporocyst. 
Figs. 8, 9. Cercaria oocysta Lebour. 
8. Sporocyst with encysted cercariae (length 0‘12 mm.). 
9. Cercaria pressed out of cyst (length 0-24 mm.). 
Figs. 10, 11. Cercaria pirum Lebour. 
10. Encysted cercaria (cyst 0'08 mm.). 
11. Cercaria pressed out of cyst (length 0'2 mm.). 
Figs. 12, 13. Cercaria linearis Lespes. 
12. Sporocyst (length 2'6 mm.). 
13. Cercaria (length 0’18 mm.). 
Figs. 14-16. Cercaria hrachyura Lespes. 
14. Young sporocyst (length 0‘2 mm.). 
15. Older sporocyst (length 1-2 mm.). 
16. Cercaria (length (0-26 mm.). 
Figs. 17, 18. Cercaria buccini sp. inq. 
17. Sporocyst (length 1’4 mm.). 
18. Cercaria (length 0'33 mm.). 
Figs. 19-21. Lepodora rachiaea (Cobb.). 
19. Sporocyst containing encysted cercariae (length 0‘60 mm.). From a 
drawing by Mr Jas. Johnstone. 
20. Cercaria pressed out of cyst (length 0'19 mm.). 
21. Young tailed cercaria. 
