PLATE XV. 
In all the Plates the following letters have the same signification. 
c. Marginal cirrus. 
cl. Cloacal papilla or opening. 
i. Intestine. 
m. Mouth. 
ma. Manubrium of the supporting stalk of the hook-apparatus. 
ov. Ovarium. 
p. Parapodium. 
ph. Pharynx. 
s. Sucker. 
t. Testicle. 
u. Hook of the hook-apparatus. 
3 Male genital papilla or opening. 
Note . — The coloured drawings show the object seven times magnified; the uncoloured drawings are drawn with the 
Oberhiiuser camera and objective 0 (Seibert and Krafft), which magnifies 40 diameters, the hook-apparatus with camera and 
objective IV., which magnifies 220 diameters, if the contrary be not expressly stated. 
Figs. 1-4. Myzostoma injlator, n. sp. 
Fig. 1. Disk of Antedon angustiradia, P. H. C. (a., anal tube; m., month), with two 
cysts A and B at the base of the arm ; magnified about 6 diameters. 
Fig. 2. Disk of Actinometra pulchellci, Pourt., sp., with a fixed cyst ( C ) not so much 
magnified. 
Fig. 3. Intestinal ramification of the female from the cyst (fig. 2). 
Fig. 4. Dwarf male from the cyst (fig. 2), from the ventral side; magnified 7 5 
diameters, r., rectum. 
Figs. 5-13. Myzostoma murrayi, n. sp. 
Figs. 5, 6. Stalked cyst from the disk of Antedon angustiradia, P. H. C., from both sides; 
magnified 5 diameters. 
Fig. 7. Diagrammatic cross section through this cyst, to show the position of the 
female ( ? ). 
Fig. 8. Cyst upon Antedon dup lex, P. H. C. , about twice enlarged. C the Myzostoma 
cyst. 
Fig. 9. Cyst ( C ) upon Antedon radiospina, P. H. C. ; magnified about 7 diameters. 
Fig. 10. Diagrammatic cross section through the latter, to show the male ( $ ) and the 
female (?) within. 
Fig. 11. The male 75 times enlarged, v., valve-like circular fold between middle 
and terminal intestine ; r. , rectum. 
Fig. 12. A hook-apparatus slightly enlarged. 
Fig. 13. The point of the hook-apparatus much enlarged. 
