



NOTES ON THE FIBRES OF CERTAIN AUSTRALIAN 

 HIRCLNID^. 



By R. von Lendenfeld, Ph.D. 



Among the numerous Sponges of the Australian shores which I 

 am examining at present, there is a series of forms which possess 

 the filaments characterising the Hircinidse. These filaments are of 

 the same shape as those of Hircina (F. E. Schulze. Zeitschrift 

 fur Wissenschaftliche Zoologie. Band XXXIII , pi. IV.), but 

 they do not appear so smooth. With high powers (Zeiss } 2 ) it is 

 possible to detect minute spots on their surface and similar spots 

 also occur on the fibres of the horny skeletons. I am rather 

 inclined to consider the latter as the expression of the Spongoblasts, 

 and I do not think it altogether impossible that Spongoblasts 

 also form the filaments and cause in some cases their spotted 

 appearance. 



In a few species I have observed filaments apparently growing 

 out from ordinary fibres. It is highly probable, that the filaments 

 get into contact with the fibre and are then fixed there by 

 succeeding layers of Spongiolin. It is however, possible that this 

 occurrence is not so accessory, in which case we would have to 

 suppose that the filaments were parts of the horny fibrous skeleton 

 of the sponge. 



Another suggestion has however occurred to me in conse- 

 quence of the observations of some Oscillarians in Ceraosponges. 

 These Oscillarians are of equal length with the filaments and of 

 similar shape, only much thicker ; and it appears not improbable 

 that these may cause the formation of the filaments in the following 

 manner : — The Oscillarians infest the Sponges and have on the 

 Sponge-tissue the same physiological effect as a grain of sand or 



