PLATE XXXII. 
Figs. 1-5. Psamma'plidium spongiforme, n. sp, 
Figs. 6, 7. Psammaplidium effrenatum, n. sp. 
Figs. 8-10. Psammaplidium retiforme, n. sp. 
Figs. 11-13. Psammaplidium jiavum, n. sp. 
a. Anus. 
ab. Abdomen. 
at. Atrial aperture. 
hr. Branchial aperture. 
br.l. Branchial lobe. 
en. Endostyle. 
i. Intestine. 
m. Mantle. 
m.h. Muscle band in mantle. 
CB. (Esophagus. 
'p.ah Post-abdomen. 
T. Kectum. 
sg. Stigmata of branchial sac. 
st. Stomach. 
t.c'. Modified test cells. 
t.f. Eibrous band in the test. 
t.m,. Test matrix. 
tr. Transverse vessel of branchial sac. 
t.v. Spermatic vesicles. 
Fig. 1. hdxgQ Q,o\onj oi Psammaplidium spongiforme ; natural size. 
Fig. 2. Ascidiozooid of Psammaplidium spongiforme, seen from right side ; magnified 
(S., 1 inch). 
Fig. 3. Part of branchial sac of Psammaplidium spongiforme, with unusually large 
stigmata ; highly magnified (S., 5 inch). 
Fig. 4. Part of another branchial sac of Psammaplidium spongiforme, showing stigmata 
of the ordinary size ; highly magnified (S., 5 inch). 
Fig. 5. Alimentary canal and post-abdomen of Psammaplidium spongiforme; 
magnified (S., 1 inch, enlarged). 
Fig. 6. Qolonj oi Psammaplidium effrenatum; natural size. 
Fig. 7. Part of mantle of Psammaplidium effrenatum; magnified (S., 1 inch). 
Fig. 8. Colony of Psammaplidium retiforme ; natural size. 
Fig. 9. Part of branchial sac of Psammaplidium retiforme ; highly magnified (S., ^ inch). 
Fig. 10. Branchial siphon and lobes of Psammaplidium retiforme; highly magnified 
(S., i inch). 
Fig. 11. Colony of Psammaplidium flavum ; natural size. 
Fig. 12. Part of surface layer of test seen from interior ; magnified (S., 1 inch). 
Fig. 13. Small portion of surface layer of test seen in section, showing the fibrous bands 
of test matrix which separate the masses of modified test cells; highly 
magnified (S., ^ inch). 
