BY R. VON LENDENFELD, PH.D. 903 



2. FAMILY. HOMODERMID^. Von Lendenfeld. 



HOMOCCELA, THE INNEH SURFACE OF WHICH IS COMPLI- 

 CATED SO AS TO FORM RADIAL SACK-SHAPED EXCRESCENCES 

 SIMILAR TO THE RADIAL TUBES OF THE SYCONID.E. (CILIATED 

 CHAMBERS ) 



I constitute this family for a small Sponge, which combines 

 characters of the Syconidaj, with those of the Asconidae. The 

 whole of the Entoderm consists of flagellate cells, and we find the 

 same Epithelium on the inner side of the Oscular tube, in the hollow 

 peduncle and even in the Entoderm of the hollow stolons, which 

 connect the different individuals of one colony ; as in the sack- 

 shaped excrescences, the homologa of ciliated chambers. Pores 

 lead from the outer water not only into the radial tubes but also 

 direct into the Gastral cavity. 



I place this family in the group Homoccela, because I consider 

 the " homodermic " character more important than the " asconic." 



Haeckel (1) has described two Sponges, namely, Ascaltis 

 canariensis and Ascaltis Lamarkii which show a similar structure 

 of the body wall. He describes papillae growing from it into the 

 gastral cavity, papillae into which the outer ectoderm is drawn and 

 which are situated in longitudinal rows. It is evident that this 

 complication is similar to the canal system of the Syconidse. If 

 these two species are not to be considered as Ilomodermidae they 

 are in any case transition forms between it and the Ascouidae 

 proper, with a simple or irregularly folded gastral cavity. 



GENUS. HOMODERMA (2). Nov. Gen. 

 Homodermidse, with acerate triradiate and quadriradiate spicules. 



HOMODERMA SYCANDRA. Nov. Spec. 



Shape : From a creeping hollow stem homologous to the 

 Hydrorhiza of Hydroids, tubes grow up which ai"e about twice as 



(1). From ofioiov Sep/xa, the same kind of skin throughout. 

 (2). E. Haeckel. Die Kalkschwiimme, eine Monographie. Band II., 

 Seite 53-54 and 6L 



