PLATE XXV. 
Figs. 1-3. Morchellium giardi, n. sp. 
Figs. 4-6. Sidnyum 'pallidum, n. sp. 
Figs. 7-9. Polyclinum molle, n. sp. 
Figs. 10-12. Polyclmum minutum, n. sp. 
Figs. 13, 14. Amaroucium hepaticum, n. sp. 
Figs. 15, 16. Aplidium crassum, n. sp. 
st. stomach. 
t.c. Test cells, 
th. Thorax. 
t.k. Terminal bulb on vessel in test. 
tr. Transverse vessel of branchial sac. 
t.v. Spermatic vesicles. 
V. Vessel in test. 
v.d. Vas deferens. 
Fig. 1. Colony of Morchellium giardi; natural size. 
at. Atrial aperture. 
db. Abdomen. 
hi. Bladder cell. 
hr.l. Lobe of branchial aperture. 
en. Endostyle. 
h.m. Horizontal membrane of bran- 
chial sac. 
i. Intestine. 
m.f. Muscle fibres. 
0. Ova. 
(B. (Esophagus. 
p.db. Post-abdomen, 
r. Eectum. 
sg. Stigmata of branchial sac. 
sg.c. Ciliated cells bounding stigmata 
of branchial sac. 
sph. Sphincter, 
Fig. 2. Part of branchial sac of Morchellium giardi; magnified (S., 1 inch). 
Fig. 3. Stomach of Morchellium giardi, showing irregular thickening of wall; magnified 
(S,, 1 inch). 
Fig. 4. Colony of Sidnyum pallidum ; natural size. 
Fig. 5. Part of branchial sac of Sidnyum pallidum ; magnified (S., 1 inch). 
Fig. 6. Ascidiozooid of Sidnyum pallidum, from left side ; magnified (S., 1 inch). 
Fig. 7. Colony of Polyclinum molle ; natural size. 
Fig. 8. Part of branchial sac of Polyclinum molle; highly magnified (S., ^ inch). 
Fig. 9. Ascidiozooid of Polyclinum molle, seen from right side ; magnified (S., 1 inch). 
Fig. 10. Colony of Polyclinum 'minutum ; natural size. 
Fig. 11. Ascidiozooid of Polyclinum minutum, seen from right side; magnified (S., 1 inch). 
Fig. 12. Part of branchial sac of Polyclinum minutum; highly magnified (S., inch). 
Fig. 13. Part of slice of colony of Amaroucium hepaticum; natural size. 
Fig. 14. Part of branchial sac of Amaroucium hepaticum; highly magnified (S., ^ inch). 
Fig. 15. Colony of Aplidium crassum; natural size. 
Fig. 16. Part of section of test of Aplidium crassum ; highly magnified (S., ^ inch). 
