66 RECORDS 01? THE AUSTRALIAN MUSEUM. 



but were of foreign origin. The spicules were examined in situ, 

 and, after boiling in nitric acid, they were found to be as follows : 

 Megaseleres, oxea, strongyla, and styli (?). 



(a) Slightly curved oxea, either abruptly pointed or tapering 

 from the middle. Size— 25 to 35, by 007 to 01-2 mm. 



{b) Strongyla, curved or sinuous. Size — 05 to 1-25, by O'OOS 

 to 0-606 mm. 



Thorecia ramsayi, Lendenfeld (No. 60), is a discoloured example 

 of Clatliriopsamma lohosa, Lendenfeld. 



Holtenia pourtalesii, Schmidt (No. 188), is according to the 

 original label in the cup of the sponge Holtenia carpenteri, Wyv.- 

 Thomson, and was obtained by "H M.S. Porcupine" in 1870. 



There are many other instances of errors in identification and 

 incorrect descriptions which will be found noted in the accounts 

 of the species. The foregoing are sufficient to show the difficulties 

 encountered in the work of identification by means of the " Cata- 

 logue of Sponges in the Australian Museum," notwithstanding all 

 the advantages in the shape of an immense collection for com- 

 parison, an extensive acquaintance with the types, and a general 

 knowledge of the Australian sponge fauna. It would be much 

 more difficult for a worker at a distance, who la(?ks the above 

 advantages. Descriptions, such as indicated in the tabular list, 

 are responsible for wrong identifications, and the augmentation of 

 synonymy. 



In proceeding with the work of determination, two courses were 

 open — one easy, the other difficult. The former course would be 

 to compare any given specimen with the type, and accept the 

 name as correct, more especially when the examples compared 

 were the exact counterpart of each other. After consultation with 

 the Curator, I decided to follow the safe or difficult method ; and 

 in all cases I tried to ascertain the whole of the characters of the 

 species before attempting its identification. This being accom- 

 plished, the description was consulted ; if this failed to agree, then 

 the type was examined, and critically compared with the example 

 selected for identification. Frequently the latter had to be laid 

 aside and a thorough examination of the type begun ; and often 

 the result involved tlie re-description of the latter, either wholly 

 or in part. Upwards of one hundred and twenty of the exhibited 

 specimens have thus been subjected to a careful microscopical 

 examination, and many sections mounted for future use. In eacli 

 case, when dealing with the Lendenfeldian collection, the specimen 

 number has been given. 



After realising the position I was placed in by the want of an 

 authentic series of named specimens, it was decided by the Curator 

 and myself to ask the assistance of Professor Arthur Dendy, of 



