der niederen Thiere während der J. 1868—1869. 361 



der nach Gray (Proceed. zool. Soc. 1868. p. 637) den 

 Halichondriaden zugehört und mit nachfolgender Diagnose 

 verzeichnet wird. 



Xylosijongia Gr. Frond compressed, fan shaped, divided 

 above into strap-shaped, flat lobes, rather wider at the ends. Root 

 an expanded disk. Stern thick, woody, subcylindrical below, coni- 

 pressed above and expanded into a flat fan-like frond, which is 

 divided above into eight or ten strap-like flat lobes like the finge rs 

 on the band, the lobos varying rather in width, the outer one on 

 each side being the narrowest. The root and stem are solid, wood- 

 like, the upper part of the broad, expanded, fan-like part of the 

 stem more or less pierced with different-sized perforations, and the 

 part divided into strap-like reticulate lobes, which are generally ra- 

 ther wider at the ends. The expanded part of the stera and the 

 strap-like lobes are all formed of parallel cylindrical filaments, about 

 as thick as twine, which in the upper part of the stem are united 

 together by woody matter, leaving only a few perforations between 

 them; but in the strap-like lobes the filaments are much more dis- 

 stinct, rather flexuous, inosculating where they meet their neighbou- 

 ring subparallel filaments, united by the woody material, which is 

 not quite so thick as the filaments. The surface is rather rugose, 

 the minute rugosities of the stem and filaments being placed lon- 

 gitudinally and parallel to each other. Spicules of one kind, minute, 

 slender, fusiform, often slightly curved or arched. Sp. n. X. Cookei 

 von unbekannter Herkunft. 



In dem IV. Catalog des Museums Godefroy wird 

 (p. XX) eines Hornschwammes aus der Bassstrasse ge- 

 dacht, der aus der obern Oeffnung einer 3— 5 Zoll langen 

 anscheinend chitinösen Wurmröhre hervorgewachsen ist. 



V. Martcns berichtet (Archiv f. Naturgesch. 1867. 

 Ö. 61 — 63. Tab, I) über einen Süsswasserschwamm aus 

 Borneo, der, wie die von Bowerbank beschriebene 

 Spongilla reticulata des Amazonenstromes, an den in das 

 Wasser hineinhängenden Baumzweigen sich ansiedelt und 

 in der trockenen Jahreszeit oft mehrere Fuss über dem 

 Spiegel des Wassers als ein faustgrosser trockner Ballen 

 mit zahlreichen grubenförmigen Vertiefungen, einem Wes- 

 penneste nicht unähnlich — daher auch Spongilla vespa- 

 rium — gefunden wird. Die Form der Kieselnadeln und 

 der Amphidisken lassen über die specifische Natur des 

 Schwammes keinen Zweifel. 



