454 
Marine Cerccvriae 
Tennant, D. Hilt (1906). A Study of the Life-History of Bucephalus haimeanus^ 
etc. Quart. Journ. Microsc. Sci. N. S. xxix. 6.35. 
Scott, T. (1909). Some Notes on Fish Parasites. ^Qth Ann. Rep. of Fish. Board 
for Scotland. 
ViLLOT, M. (1878). Organisation et developpement de quelques especes de Trema- 
todes endoparasites marins. Ann. des Sci. Nat. Zool. (6 Ser.) vin. 18. 
Williamson, H. C. (1911). Notes on the Eggs of the Angler etc. 'i&th Ann. Rep. 
of Fish. Board for Scotlaiid. 
DESCRIPTION OF PLATES XXV TO XXIX. 
The folloiving letters apply to all the figures. 
C. cercaria. 
C.G. eystogenous glands. 
C.O. eystogenous organs. 
C.8. cirrus sac. 
E. eye. 
E. V. excretory vesicle. 
G. gland cells. 
G.A. genital aperture. 
I. intestine. 
L.C. lateral canal. 
O. ovary. 
OD. oviduct. 
(ES. oesophagus. 
O. S. oral sucker. 
P. pharynx. 
P.PH. prepharynx. 
S. sporocyst. 
S.G. stylet glands. 
S. G.D. ducts of stylet glands, 
ST. stylet. 
T. testis. 
V. vitellaria. 
V.B. vas deferens. 
V.S. ventral sucker. 
PLATE XXV. 
Figs. 1-4. Gasterostomum gracilescens (Eud.). 
1. Portion of sporocyst (length 1 mm.). 
2. Bucephalus haimeanus (length 0-3 mm.). 
3. Encysted cercaria (long axis 0‘6 mm.). 
4. Cercaria pressed out of cyst (length 2'6 mm.). 
Figs. 5, 6. Gasterostomum sp. 
5. Portion of sporocyst. 
6. Bucephalus syndosmyae sp. inq. (length 0-26 mm.) 
Figs. 7, 8. Gyjnnophallus sp. 
7. Part of cockle from under umbo containing sporocysts with cer- 
cariae. 
8. Cercaria margaritae sp. inq. (length 0-2 mm.). 
Fig. 9. Cercaria scrivenensis sp. inq. (length 0‘4 mm.). 
Fig. 10. Cercaria glancLosa Lebour (length 0’2 mm.). 
Fig. 11. Cercaria macomae Lebour (length 0-7 mm.). 
Fig. 12. Cercaria strigata Lebour (length 0'3 mm.). 
PLATE XXVI. 
Figs. 1, 2. Cercaria dichotoma Muller. 
1. Sporocyst (length 1 mm.). 
2. Cercaria dichotoma Miiller (length 0’2 mm.). 
