132 
spongin-net; 2 . by having most often more spicules in the row 
in the fibres; 3. by the spongin not being so dominating; 4. by the 
much thicker and stouter megascleres. 
Genus Toxochalina, Ridley. 
Toxochalina difficilis nov. sp. 
Carnley Harbour. 45 f. Sandy clay. 6/XII.1914. 
Several specimens; attached to shells; long cylindrical bodies, 
a little ramified; length of a specimen ca. 135 mm, thickness ca. 5 
mm. Surface a little rough on account of protruding spicules and 
small granules. Dermal membrane very delicate, pellucid. Oscula 
ca. 1,5 mm in diameter, ostia ca. 0,io mm. Consistence very soft, 
elastic. Colour gray. 
Skeleton consists of very well developed spongin-fibres wherein 
the spicules are completely enveloped. Main fibres contain 2—3 
rows of oxea, secondary fibres only one row. In the main fibres 
the spicules are always so situated that the distal end of a spicule 
touches or overhangs the proximal end of the following, while in 
the secondary fibres the spicule may be separated by a spicule- 
less interspace up to the length of one spicule. From the spongin- 
network which is parallel with and supporting the dermal-membrane, 
spicules are projecting perpendicularly through the surface of the 
sponge, making it finely shaggy; thus these spicules are not imbedded 
in spongin, in contradistinction to all other spicules in the sponge. 
Spicules: (fig. 14a—b) 1. oxea, rather stout, about 80 p by 
8,5 — 9 P, slightly curved, sharply and rather abruptly pointed; there 
are however found all transitory stages between these sharppointed 
oxea (which are by far the most numerous) and the well formed 
strongyla; length of these latter a little smaller than of the oxea. 
on account of the missing points; thickness the same. 2 . toxa!' 
much varying, both in shape and in size; a few are almost formec 
as sigmata; length 20—40 p by 0,5 1 p- 
Here we have one of the many cases, where the difficultie^ 
in classifying amongst the Monaxonida are clearly seen. The 
structure of the skeleton as well as the shape of the oxea are ex 
actly as in Chalina; while the sponge, if the microscleres are h 
be decisive for classification is to be included amongst the Gel 
liinae. 
