Spong, 1 
XVII. SPONGI/E. 
BY 
Professor 11. yon Lendenfeld. 
CONTENTS. 
Page 
Introduction 1 
I. Titles 2 
II. Biology. 
1. Morphology and Physiology 
a. General 6 
B. Canal-system .... 6 
c. Skeleton 0 
p. Epithelia and Cuticula . 7 
E. Cortex 7 
F. Interstitial layer ... 7 
G. Sexual cells, Propagation 
and Development . . 8 
H. Physiology 9 
I. Habits, Bionomics . . 9 
K. Artificial Spongeculture 10 
2. Geographical Distribution 
A. General 11 
b. Faunistic 11 
3. Geological Distribution. . 12 
4. Phylogeny & Classification 12 
Page 
5. Methods 12 
III. Systematic. 
Calcarea 
Homoccela. . . . . .13 
Heterocoola 13 
Silicea 
Triaxonia 13 
Hexactinellida . 13 
Hexaceratina . . . 14 
Tetraxonia 14 
Tetraxonida . . . .14 
Tetractinellida . . 14 
Lithistida. .... 14 
Monaxonida . . . .14 
Clavulina ... 14 
Cornacuspongifo . .15 
Marine forms . .15 
Spongillidae . . 15 
Doubtful forms 15 
INTRODUCTION. 
The most important papers on Sponges published in 1896 are : — (18) in 
which Hjeckel gives his ideas concerning the structure, the individuality, 
the phylogeny, and classification of Sponges ; (36) in" which Minch in 
deals with the classification of the Asconidce ; (43) in which F. E. Schulze 
introduces several new Hexactinellids to science, and proposes some 
alterations in the arrangement of previously described forms ; (8, 9, 10), 
(22), (24), (27), aud (49, 50), in which Breitfuss, Ijima, Kieschnick, 
Lambe, and Topsent, describe a number of new species from the 
