10 



BRITISH SPONG1AD.E. 



Genus XXI. HALICHONDKIA. 

 Section *. Skeleton spicula acerate. 

 Sub-section A. Dermal membrane aspiculous. 

 1. Halichondria Maclntosbii. | 2. Halichondria regularis. 



Sub-section B. Spicula of dermal membrane dispersed. 



3. Halichondria caduca. 



4. ,, inconspicua. 



5. incerta. 



6. Halichondria coalita, 



7. ,, mutula, 



8. ,, cylindracea. 



Sub-section C. Spicula of dermal membrane reticulated. 



9. Halichondria panicea. 



10. ,, g-labra. 



11. ,, augulaui. 



12. ,, distorta. 



13. ,, edusa. 



14. ,, auibigua (inul- 



tispiculous). 



15. Halichondria Couchii (uni- 

 spiculous). 



1<>. Robertsoni. 



(fasciculated). 



17. ., condensa(mul- 



tispiculoas). 



18. coralloides. 



Section **. Skeleton spicula acuate. 



Sub-section A. Skeleton spicula smooth. Dermal spicula dispersed. 

 19. Halichondria Thompson!. 



20. 

 21. 



forceps, 

 simplex. 



22. Halichondria subdola. 



23. foliata. 



Sub-section B. Skeleton spicula smooth. Dennis reticulated. 

 24. Halichondria corrugata. 26. Halichondria flabellifera. 



25. 



falcula. 



Section ***. Skeleton spicnla spinous-acuate. Dermal spicula more 



or less fasciculated. 



Sub-section A. Spicula of dermal membrane fasciculated. 



27. Halichondria incrustans. 



28. 

 29. 

 30. 

 31. 

 32. 

 33. 



Candida. 



irregularis. 



Dickiei. 



Pattersoni. 



pulchella. 



Ingalli. 



34. Halichondria scandens. 



35. 

 36. 

 37. 



38. 

 39. 



Batei. 



nigricans. 



albula. 



expansa. 



virgea. 



