592 DR. R. VON LENDENFELD ON THE SysTEMATIC [Dee. 21, 
With proper spicules in the supporting skeleton. 30. 
(17.), Without proper spicules in the supporting 
BKGLStOR: Macatee ee cscce len sotont tee (31.) 
With uniformly distributed skeleton - reticu- 
lation and not very large subdermal cavities. 32. 
30. The skeleton consists of a dense axial reticu- 
lation and isolated fibres extending from this 
to thesurface. Between these very extensive 
( subdermal cavities are situated .............4. (33.) 
With gemmulz ; living in fresh water ......... 37. Spongillide. 
82. { Withees BOMATIUID oo 5005, Soeeecediaveusentadeseeeee 34. 
Without flesh-spicules : fibres of the supporting 
skeleton not spined ............ssssecseesseesneee 38. Homorhaphide. 
34. { Flesh-spicules sigmata or spiral ; no chele...... 39. Heterorhaphide. 
Flesh-spicules chele; when absent, fibres of 
| supporting skeleton HPUWIOU pecwarces se soe cnecoet 40, Desmacidonide. 
(33.)7 Nop chelie cies: Ae aie ee See 41, Avinellide. 
With small spherical chambers and opaque 
(31.) Pround-sapstance .2.....c--.se.cse- ocd sene-eosee== 35. 
‘/ | With large sac-shaped chambers and trans- 
parent ground-substance ............:s.seeeeees (36.) 
35 Without filaments in the ground-substance ... 37. 
: { with filaments in the ground-substance......... 38. 
37 Skeleton-fibres with thin axial canal ............ 42. Spongide. 4 
Skeleton-fibres tubular, with thick pith ..,...... 43. Aplysinide. 
(88.) Skeleton-fibre with thin axial canal ............ 44, Hircinide 
Skeleton-fibres with thin axial canal ; reticulate 45. Spongelida. 
(36.) 4 Skeleton-fibrestubular with thick pith; dendritic 46. Aplysillide. 
INoiskeleionte.s2-sc.scssacoseas .0> sarenehies.eeecee eee 47. Halisarcide. 
APPENDIX. 
LIST OF PUBLICATIONS RELATING TO THE SPONGES. 
(Explanations of the Abbreviations used are appended.) 
1. #lianus, Claudius. [epi Zowyv. Liber 8, Cap. 16. 
2. see Alexander, (On Hexactinellids.) Bull. Mus, C. Z. 1868, p. 367 
(1868). 
3. Aldrovandi, U. De reliquis animalibus exanguibus nempe de Mollibus, 
Crustaceis, Testaceis et Zoophytis libri quatuor. Bononia, 1606. Fol. 
(2nd ed. 1618; 8rd ed. 1623; 4th ed. 1642.) (1606-1642. ) 
