STUDIES ON THE COMPARATIVE ANATOMY OF SPONGES. 161 



necessary diagnoses till later on. The following, then, is the 

 classification proposed : 



Families. 



1. Leucascidse 



2. Sycettidse 



3. Grantidse 



4. Heteropidse. 



I 

 5. Amphoriscidse . . <{ 



Genera. 



1. Leucascus. 



2. Sycetta. 



3. Sycon. 



4. Sycantha. 



5. Grantia. 



Sub-genus Grantiopsis. 



6. Ute. 

 Sub-genus Sjnute. 



7. Utella. 



8. Anamixilla. 



9. Sycyssa. 



10. Leucandra. 



11. Lelapia. 



12. Leucyssa. 



13. Grantessa. 



14. Heteropia. 



15. Vosmaeropsis. 

 ri6. Heteropegma. 



17. Amphoriscus. 



I 18. Syculmis. 

 l_ 19. Leucilla. 



Before concluding these introductory remarks it is my 

 pleasant duty to express my sincere thanks to various friends, 

 without whose assistance this paper could not have been 

 prepared. To Mr. J. Bracebridge Wilson, M.A., I owe, as 

 usual, the greater portion of my material, and I am also 

 indebted to Professor W. Baldwin Spencer, Mr. T. Whitelegge, 

 and the authorities of the Adelaide Museum for a number of 

 very valuable Australian sponges; while numerous fragments of 

 type specimens from the British Museum, most generously 

 forwarded to me by Dr. Giinther, have been of the greatest 

 service. Lastly, I must again thank Professor G. B. Howes 

 for most kindly undertaking the correction of the proof in my 

 absence from England. 



The numbers in parentheses, in the text, refer to the list of 

 literature at the end. The technical descriptions of a large 



