PLATE XLTIL 
PAGE 
Figs. 1-9. Scolopes moseleyi, . . .432 
Figure 1. The sponge; nat. size. 
„ 2-7. Spicules — 
Fig. 2. Oxea of the spicular fibres ; 
X 51. 
„ 3. Oxea of the cortex ; x 51. 
,, 4. Microxea of the cortex and 
choanosome; x 51. 
/ 
Figs. 5-7. Amphiasters ; x 720. (In 
fig. 6, three whorls of 
actines are present, it thus 
calls to mind the scep- 
trella). 
8. Transverse section through the cortex, to show the arrangement of 
the spicules; x 51. 
9. A part of the preceding, more highly magnified, to show the arrange- 
ment of the microxeas ; x 200. 
Figs. 10-12. Isops apiarium, . . . 268 
10. Diactinate reductions of the oxyaster ; x 225. 
11. Mierostrongyle ; x 225. 
12. Oxyaster; x 225. 
Figs. 13-19. Miscellaneous. 
„ 13. Part of a radial section through a very young example of Drag- 
mastra normani, showing the dichotriaenes beneath the outer 
epithelium, with very short rhabdomes ; x 200. 
,, 14, 14a. Two triods from Placina monolopha, showing a sigmate form at the 
origin; fig. 14 x 540; fig. 14a x 1080. 
„ 15. Transverse section through the cortex of Tethya lyncurium, showing 
segmented ova, or developing internal buds, situated immediately 
beneath the outer epithelium ; x 6^. 
,, 16. A part of the preceding more highly magnified, to show the structure 
of the segmented ova or internal buds ; x 292. 
,, 17. Part of a radial section through a specimen of Tethya lyncurium 
from Norway. The oscule communicates with the excurrent canal 
by a sieve-pore ; x 10. 
,, 18. The terminal portion of an oxea of Dorypleres dendyi (wrongly 
assigned to Tethya lyncurium in the legend to the Plate) after 
treatment with hydrofluoric acid ; the outer brown dotted line is 
an organic sheath which resists solution, the inner brown rod is 
the axial rod of the spicule ; x 292. 
„ 19. A dichotrisene of Dragmastra normani, with an adventitious cladus. 
Two of the normal dichocladi (6 and c), are not completely repre- 
sented in order to save space ; a is the accessory cladus, its axial 
rod is separate and distinct from that of the rest of the spicule ; 
X 200. 
