BY R. VON LENDENFELD, PH.D. 



The sexual products. 



Ova and Sperraatophores, that is to say, masses of Sperma- 

 tozoons enclosed in a kind of sack ai^e found abundantly and 

 exclusively in the threads of the Gastral cavity. Polejaeff (1) 

 has given a new explanation of the formation of these masses of 

 Spermatozoons, and I am inclined to believe that the Spermato- 

 genesis described by that author from Sycandra also holds good in 

 the case of our Bajalus. 



Ova and Spermatozoa are never found in one and the same 

 specimen, but that is no reason why this Sponge should not be 

 hermaphroditic all the same, as it is not altogether improbable 

 that the male and female products are matured in the same 

 specimens at diiferent times. 



The fact that the sexual products are massed in the interior 

 of the Sponge, in the exhalent canal system, shows that our 

 Sponge is in this particular similar to Aplysilla (2), and 

 particularly to Oscarella lobularis (3). 



We find that in our Sponge there is, if my hypothesis (4) 

 regarding the digestion of Sponges be accepted, a digestive cavity 

 below the skin — the subdermal cavity — a breathing and excretary 

 zone below this — the ciliated chambers — and a kind of very little 

 differentiated sexual organ in the centre — the gastral threads — 

 whilst the " Gastral cavity " has the function of a breeding place, a 

 marsupium. 



Locality : South Coast of Australia, Port Phillip, Von Lenden- 

 feld. Pretty rare in the laminarian zone attached to stones. 



Season : The Sponge was found repeatedly with sexual products 

 in August and September. At that time and also at other times 

 specimens without sexual products were obtained. 



(1) iV. Polejaeff. Die Spermatogenese bei Sycancka raphanus. Sitzungs- 

 berichte der Kaiserlichen Academie der'Wisenschaften in Wien, Mathema- 

 tisch-Naturwissenschaftliche Classe. Band LXXXVI., Seite 278. 



(2) B. V. Lendenfeld. L.c. Tafel XL , fig. 14. 



(3) F. E. Schulze. Die Gattung Halisarca, Zeitschrift fiir wissenschaft- 

 liche Zoologie. Tafel IV., fig. 20, 



(4) B. V. Lendenfeld. The Digestion of Sponges Ectodermal or Ento- 

 dermal. Proceedings of the Linneau Society of New South Wales. Vol. 

 IX., p. 434, ff. 



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