B. Porifera incalcaria. 5 



Lendenfeld (') fed sponges with milk, starch and carmine ; they were then at 

 various stages prepared and dissected. The same was done with poisons (mor- 

 phinum, strychnin, digitalin, veratrin , curare and cocain). On the whole 149 

 experiments were made on 18 sponge-species from Trieste. The results are: 

 Solid bodies, like carmine and starch, effect a contraction of the pores. After 

 2-3 hours the pores open again. Milk generally does not effect any contraction 

 of the pores. Carmine and milk are taken in by the flagellated cells. Starch- 

 granules are too big. After two days carmine is pushed out, not being digestible. 

 Milk-globules are kept and carried away by the chorocytes (Wanderzellen) . The 

 author concludes that food is taken in by the innermost parts of the sponge, and 

 not (as he formerly believed) by the external surface. If this happens, it is patho- 

 logical. Poisons or, in general, harming influences, effect contractions of certain 

 parts, especially of the sphincters of the pores. - - See also Krukenberg, Marchal, 

 and Schneider. 



Maas studied the development of Spongilla, especially the epiblast. Contrary 

 to Goette, he finds that the epiblast of the Spongilla-larva is not lost, but is 

 modified into the flat epithelium of the young sponge. Vosmaer {^} be- 

 lieves the same and found it to be the case in Myxilla sp. He warns against 

 using the terms ectoderm, epiblast etc., but he states that the flagellated cylin- 

 drical epithelium of the larva loses its flagella, becomes more and more cubical 

 and finally in the young sponge is seen as pavement-epithelium; this process 

 begins at the pole where the larva is fixed. Between the cubical cells are gland- 

 cells, by means of which the animal is fixed. The inner mass shows gradually 

 more intercellular substance ; in it, after a time, there appear fissures, close under 

 the free surface ; they become lined by endothelium and give rise to the sub- 

 dermal cavities. A little later other canals appear in the same way, as also the flagel- 

 lated chambers ; they do not originate from one central cavity , although the 

 epithelium of such a cavity, in the adult sponge, is repeatedly described as 

 entoderm. After the appearance of the flagellated chambers, the spicules 

 arrange themselves into bundles and the first traces of spongin become visible. 



Carter ( ! ) gives an account of the occurrence of sponges in various geological 

 periods. It astonishes the author that Ceratina, so very abundant r& recent 

 periods, do not occur in the fossil state. 



Katzer states that sponges are very abundant in the Devonian layers of Bohemia. 

 Es gibt kein Kalksteinstockwerk im mittel-bohmischen Silur und Devon, wel- 

 ches Spongienreste nicht enthielte. - - See also Bucher. Davvson. and Geinitz. 



B. Porifera incalcaria. 



I. Hyalospoiigiae. 



See Geinitz. 



Kirkpatrick mentions Aphrocattistes bocagei from the S.W. Coast of Ireland. 



II. Spicnlispongiae. 



(A. Lithistina.) 



B. Tetraxonina. 



See, sopra p 3, Hanitsch, and, p 4, Lendenfeld ( 6 , 2 ). 



Sollas states that his definition of Synops does not agree with Vosmaer's type- 

 specimen. Hence he proposes to bring S. neptuni Soil, to the new genus Sidonops. 

 As to the true Synops, he believes this genus identical with hops. 



Zool. JaliresTsericht. 1889. Porifera. C 



