BY R. VON LENDENFELD, PH.D. SOT 



are uniformly conulated. The conuli are about 1 mm. high, and 

 2 mm. apart from one another. At the bottom of the peduncle 

 the conuli are nearer to one another than further up. There is no 

 difference in the conulation of the peduncle and head. 



Structure. 



With the exception of the dermal lamella, the microscopic 

 structure is very similar to that of Halme Nidus Vesparam 

 described above. In other respects this sponge shows greater 

 affinities to Aulena. The true body of the sponge consists of a 

 network of thick, cylindrical, longitudinally disposed fibres which 

 coalesce very frequently. They measure 5-8 mm. in diametei^, 

 and form a dense network supported by the peduncle. Throughout 

 these, as also in the peduncle we meet with a canal system and 

 skeleton similar to that of Halme Nidus Vesparum. The inhalent 

 pores are found abundantly on the exposed parts, whereas the 

 Oscula are all directed inward towards the Pseudogaster. At the 

 top of the peduncle there are several larger Oscula. There 

 are no Oscula on the sides of the peduncle. Evidently here 

 the Pseudogaster is being converted into a true Oscular tube, 

 and if the apertures between the fibres of the true sponge 

 body were filled up we would have a sponge before us with 

 a simple terminal Osculum. The thinking reader can draw 

 his own conclusions from these statements. It may, however, be 

 of interest here to mention the variety in shape in a sponge which 

 I have named Cacospongia exemplum. Over a hundred specimens 

 of this sponge have passed through my hands, There are numerous 

 varieties, but all are connected with one another in such a manner 

 by intermediate forms that they altogether represent a continuous 

 series, special forms of which have been described by Hyatt and 

 Carter from Australian waters. In the first variety C. ex. prima, 

 we have flat, expanded frondose forms. All the Oscula are on one 

 side. In the second, (C. ex. secunda) we have a true cup formed by 

 the bending and final coalescing of the lateral margins of this plate. 

 All Oscula are on the inner side. Geelongia Vasiformis, Carter, 

 is identical with this variety. Further the cup becomes smaller 



