446 ^- ^- J- Vosinaer 



b. Groimdsnbstance between the ciliated Chambers not gra- 

 nular 5. (fam. Spongelidae) . 



4 a. Skeleton formed by a more or less regulär network of 

 concentric layers; axis-substance of the fibres abundant; 



without sand fam. Aplysinidae. 



b. Skeleton formed by an irregulär network; axis-sub- 

 stance hardly visible ; main fibres nearly always with 



sand. Wide canals and lacunae fam. Spongidae. 



5a. No sand in the fibres: skeleton rather regulär . . . . Velmea. 

 b. Main fibres with much sand; skeleton not very regulär Spongelia. 

 The diaguosis of the genus Velmea may be given as follows: ske- 

 leton formed by a regulär (sex-radiate) network of spon- 

 gin-fibres that are destitute of sand or other foreign sili- 

 ceous, or calcareous bodies. The shape of the ciliated Chambers 

 and the arrangement of the canalsystem have the character of the family 

 Spongelidae. 



The name Velinea, arose in the follo wing manner. I had named 

 this sponge Evelina but afterwards seeing that this name had already 

 been appropriated, I transposed the letters. 



Explanation of Figures. 

 Piatesi. 



(The object is preserved in strong alcohol and stained with borax-carmine. I used 

 Microsc. Hartnack ; Cam. lue. of Zeiss-Oberhäuser ; Immersion of Seibert & 



Kraft.) 



Fig. 1. Velinea gracilis n. g. ; n. sp. Nat. size. 



Fig. 2. Surface, seen with a pocket-lens. 



Fig. 3. Epithelinm of the outer parts. ]) pores. Hartn. VII. 



Fig. 4. Transverse section. Combination of two or three following sections 



s.cZ.c. subdermal cavity; i.e. inhalant canal ; e.c. exhalant canal. Somf 



of the ciliated Chambers are cut, others are intact, showing the Chamber 



pores. Hartn. III, cam. lue. projected on the level of the object stage 

 Figs. 5 and 6. Sections of ciliated Chambers in communication with the canals 



Letters as above mentioued. Hartn. IV, ocul. tube extended. Proj. obj 



stage. 

 Figs. 7, 8 and 9. Diflferent shapes of ciliated Chambers. Hartn. IV, tube extended 



Proj. obj. stage. 

 Fig. 10. Epithelium-cellslining the cloacal tube. Imm.VII. Ocul. 3. Proj. obj. stage 

 Fig. 11. Transverse section of skeleton-fibre. Imm. VII etc. as in fig. 10. 

 Fig. 12. Longitudinal section of id. Magnif. id. id. 

 Fig. 13. Longitudinal section of id. after having been treated by Eau de Javelle 



Magnif. as in 12. 



