2 Spong. 
XVII. SPONGIiE. 
[ 1904 ] 
Page 
f. Miscellanea 10 
(i) Bibliography . 10 
(ii) Technique 10 
(iii) Economics 10 
(iv) Classification 11 
(v) Chemistry of Sponges 11 
III. Distribution. 
a. Geographical 11 
«. Marine 11 
(i) General 11 
(ii) Atlantic Ocean and Adjacent Seas . . . 11 
(iii) Indian Ocean and Adjacent Seas . . . 11 
(iv) Pacific Ocean and Adjacent Seas . . . 11 
(v) Arctic Seas (vacant). 
(vi) Antarctic Seas 11 
/3. Freshwater 11 
b. Geological . . . . . . . . . 11 
(i) General (vacant). ... 
(ii) Cainozoic . . . . . . . . 11 
(iii) Mesozoic . . . . . . . . 11 
(iv) Palaeozoic 12 
IV. Systematic. 
a. Porifera, general . . . ... . . . 12 
b. Calcarea (including Astroscleridce) 12 
(i) Homoccela . 12 
(ii) Heterocoela 12 
c. Hexactinellida 13 
(i) Lyssacina 13 
(ii) Dictyonina 16 
D. Demospongioe 18 
(i) Tetraxonida . 18 
(a) Carnosa 18 
(b) Tetractinellida 18 
(1) Choristida . „ „ . . . 18 
(2) Lithistida 19 
(ii) Monaxonida 21 
(a) Hadromerina 21 
(1) Aciculina . . . . . 21 
(2) Clavulina . . . . 21 
(b) Halichondrina 22 
(iii) Keratosa ........ 25 
(a) Dictyoceratina ...... 25 
(b) Dendroceratina .26 
. (iv) Myxospongida 26 
e. Octactinellida (vacant). 
F. Heteractinellida (vacant). 
Q. Incertaj Sedis 26 
