100 A MONOGRAPH OF THE 



Genus D i ctyo cyli n d rus , Bowerbank. 



Section * Skeleton spicula, acerate and acuate. 



1. Dictyocylindrus ventilabrum, Bowerbank. 



2. ramosus, Bowerbank. 



3. radiosus, Bowerbank. 



Section * * Skeleton spicula, acuate. 



4. Dictyocylindrus Howsei, Bowerbank. 



5. hispidus, Bowerbank. 



6. aculeatus, Bowerbank. 



7. fascicularis, Bowerbank. 



8. viryultosus, Bowerbank. 



Section * * * Skeleton spicula, spinulate. 



9. Dictyocylindrm pumilus, Bowerbank. 



Section * * * * Skeleton spicula, cylindrical. 



10. Dictyocylindrus stuposus, Bowerbank. 



11. ruyosus, Bowerbank. 



1. Dictyocylindrus ventilabrum, Bowerbank. 



Sponge. Pedicelled, ramose, fan-shaped ; surface hispid ; 



branches dividing dichotomously, rarely trichotoinously. 



Oscula and pores inconspicuous. Skeleton. Spicula 



acuate and acerate, elongate, often flexuous. External 



defensive spicula attenuato-acuate, long and stout. 



Tension spicula fusiforrni-acuate or acerate, slender. 



Internal defensive spicula attenuato-acuate, entirely 



but minutely spined. 

 Colour. Alive, bright orange yellow. Buff yellow in the 

 dried state. 



