PLATE XXVI. 
Figs. 1-4. Polyclinum 'pyriforme, n. sp. 
Figs. 5-7. Polyclinum depressum, n. sp. 
Figs. 8, 9. Aplidium fumigatum, n. sp. 
Fig. 10. Polyclinum incertum, n. sp. 
Figs. 11, 12. Amaroucium alhidum, n. sp. 
ab. AbdomeB. 
at. Atrial aperture. 
hr. Branchial aperture. 
en. Endostyle. 
h.m. Horizontal membrane of branchial 
sac. 
i. Intestine. 
i'. Constriction between intestine and 
rectum. 
1. Dorsal languet. 
m.f. Muscle fibres. 
fig. (Esophagus. 
p.ah. Post-abdomen. 
T. Kectum. 
sg. Stigmata of branchial sac. 
st. Stomach. 
t.c. Test cells. 
t.c'. Modified test cells. 
th. Thorax. 
t.m'. Test matrix. 
tr. Transverse vessel of branchial sac. 
v.d. Vas deferens. 
Fig. 1. Colony of Polyclinum pyriforme ; natural size. 
Fig. 2. Part of branchial sac of Polyclinum pyriforme; highly magnified (S., ^ inch). 
Fig. 3. Part of dorsal edge of branchial sac of Polyclinum pyriforme, showing 
languets; highly magnified (S., inch). 
Fig. 4. Ascidiozooid of Polyclinum pyriforme, seen from right side ; magnified 
(S., 1 inch). 
Fig. 5. Colony of Polyclinum depressum, seen from upper surface; natural size. 
Fig. 6. Ascidiozooid of Polyclinum depressum, seen from left side ; magnified (S., 1 inch). 
Fig. 7. Another Ascidiozooid of Polyclinum depressum, seen from right side ; magnified 
(S., 1 inch). 
Fig. 8. Oo\onj oi Aplidium fumigatum; natural size. 
Fig. 9. Part of test of Aplidium fumigatum; highly magnified (S., ^ inch). 
Fig. 10. Colony of Polyclinum incertum; natural size. 
Fig. 11. Colony of Amaroucium alhidum; natural size. 
Fig. 12. Part of section of colony of Amaroucium alhidum, showing transverse sections 
of the post-abdomen of Ascidiozooids ; magnified (S., 1 inch). 
