PORIFERA. I. 



thorough stud\- of tlie Chaliiiiiuv^ as tlie wliole material has only comprised six species belonging to 

 three genera. 



The Clialinince are forms generally found in more shallow water, although a few species reach 

 to a depth of ca. 150 fathoms. 



A phenomenon frequenth- seen in the C/ia/iiu'iue and with special distinctness in dried speci- 

 mens where only the skeleton is left, is a formation like yearly rings. In longer branches they are 

 often seen in great numbers above each other, their form most frequently more or less resembling a 

 conical surface. If a branch is cut through, one or more concentrical rings will be seen. These 

 vvearly rings* are formed by the meshes of the skeletal net being in these places finer than in other 

 places, and especially by the presence of more transversal fibres than in the part just inside of the 

 spot, and in this respect these layers are constructed in the same \va\' as the surface. The phenomenon 

 evidently is one of growth. It has already been mentioned by Bowerbank (Mon. of. Brit. Spong. 

 I, 152) who also thinks it to be a phenomenon of growth. 



Pachychalina O. Schmidt. 

 The form lobose or digitate^ branched or unbrauched^ the sponge solid. The fibres polyspicular 

 luith more or less spicules. Spongiii differently developed. 



I. P. Schmidtii n. .sp. 

 PL I, Figs. I, 2. PI. VIII, Figs, i, 2, 3. 

 Club- or Jingershaped. The fibres fonniiig a rather regular skeleton of primary longitudinal 

 fibres a)id secondary transverse fibres., the meshes mostly rectangular. The longitudinal fibres ruith 

 numerous spicules., the transverse fibres most frequently zvith fcTver spicules ; always a distinct spongin- 

 sheath. Oscula spread on the surface, sometimes zvith a tendency to a marginal position. Spicules 

 0-178— o-2o8""". 



The specimens in hand of this species are unbranched, finger- or clubshaped, in the lower part 

 generally narrowed to a short stalk. The specimens are of about the same size, of a length between 

 80 and 100™'", and a diameter of about 15 — 30"™. A specimen which I take to be a young one, and 

 which is attached to a shell, is much sjnaller; it is cushionshaped and has a height of 10""". The 

 colour (in spirit) is vellowish grey. The consistency, as in most ChalinincB, is firm, but very elastic. 

 The surface is even, but not quite smooth, the ends of the primary fibres rising a little above the 

 skin. The dermal membrane is transparent and very thin, and consequentU' it is often lost; jud- 

 ging b>- what I have been able to observe, it has no spicules and rests on the skeleton below, the 

 ends of the primary fibres rising through it. Oscula are scattered on the surface, in some places more 

 thickly than in others, and in one specimen that is somewhat compressed, a tendency towards a mar- 

 ginal position of the oscula is to be perceived. The openings of the oscula are almost circular, with 

 a diameter of from a little more than i"""to3""", their edges are often somewhat rising. I have not ob- 

 served the jjores, as the skin was mostly wanting in the specimens. 



The skeleton consists of stout polyspicular fibres of a thickness of 0-09— o-i6""'. There is always 

 a copious and distinct mass of spongin; in some fibres the spicules are very numerous, and then the 



