176 CEYLON PEARL OYSTER REPORT. 



I have also seen three small isochelse about O'OIS millim. long, and two or three 

 sigmata, one of which measured about 0'05 millim. from bend to bend ; but these 

 spicules are so scarce that I am doubtful whether they are proper to the sponge. 



This is an interesting species, having (if we leave out of account the doubtful 

 microscleres) the spiculation of an Ecliinodictyum combined with the habit of an 

 Echinoclathria. It is evidently nearly related to THIELE'S Echinodictyum cavernosum 

 from Celebes (39), but differs in its pale colour and in the presence of the large styli. 



R.N. 325 (Ceylon seas). 



Aulospongus, NORMAN. 



Massive Ectyoninee with plumose columnar skeleton, comprising both smooth and 

 spined styli in the spiculation. Without microscleres. 



In my ' Report on a Second Collection of Sponges from the Gulf of Manaar ' (3) I 

 expressed the opinion that NORMAN'S genus Aulospongus (55) was unnecessary, and 

 that the species for which it was established might be included in the genus Axinella. 

 Further consideration has, however, induced me to alter my views on this question, 

 and to consider the presence of the spined styli as constituting a sufficient generic 

 distinction from Axinella, and, indeed, necessitating the removal of the genus to the 

 Ectyoninae. 



This genus is evidently closely related to Raspailia, and constitutes one of the 

 apparent connecting links between the Ectyoninae and Axinellidse. THIELE (39) has 

 referred to the genus Raspailia two or three Japanese species, one, at least, of which 

 (Raspailia (?) villosa) should perhaps be included in Aulospongus. The Australian 

 Raspailia cacticutis (vide DENDY, 10) may also possibly belong here, and likewise 

 Mr. CARTER'S Dictyocylindrus sessilis from the Gulf of Manaar (4). 



Aulospongus tubulatus (BOWERBANK). 



1873, Haliphysema tubulatum, BOWERBANK (8); 1878, Aulospongus tubulatus, NORMAN (55); 

 1889, Axinella tubulata, DENDY (3). 



There are a number of specimens of this sponge in Professor 

 HERDMAN'S collection. The species (fig. 3) forms one of the 

 most characteristic elements in the Sponge-Fauna of Ceylon, 

 and is of especial biological interest as affording an example 

 of symbiosis, or perhaps commensalism, between a Sponge 

 and an Annelid. I have nothing to add to the account which 

 I gave in my ' Report on a Second Collection of Sponges 

 from the Gulf of Manaar ' (3). 



Maiiaar; nat. size. Manaar (Stats. V., IX., XV., LV., LXL, LXVIIL). 



