PORIFERA. II. 55 



111 the first instance divide again, and the new-formed branches divide also. In one specimen one 

 branch divides into three, sending off two lateral branches while the principal one itself continues in 

 the middle. In another specimen a coalescing of two stalks has taken place; as the lower part of 

 the specimen is wanting it cannot be seen, whether the two branches belong to one individual, or 

 two different individuals are coalesced. The stalk is somewhat widened below and has been attached 

 to some firm object. The stalk may be straight or somewhat curved, and it is about cylindrical. On 

 the ramifications lateral branches are found more or less extensively; they are generally only found 

 on the outmost ramifications, sometimes also some way down the branches below the last division. 

 Thus in the smallest specimen, which has only two branches, they are found some way down the 

 stalk The lateral branches are small, almost scale-like and most frequently very much directed 

 upwards, sometimes almost quite adpressed. They are arranged in several rows, but very irre- 

 gularlv, so that the rows in some places are close together, while at other places the intervals are 

 greater. The axis is slightlv compressed in the parts carrying lateral branches. The branches end with 

 a compressed part forming an extended, and on account of a little notch somewhat heart-shaped, head. 

 Perhaps the question is only of a beginning new cleaving. In a single fragment the last ramifications 

 end without this head, and this is perhaps a specimen in which the growth has ceased. The stalk 

 has a thin coating of the common nature, and this layer generally reaches far up, often to the last, or 

 last but one, division. The largest specimen in hand, the above mentioned most richly branched one 

 has a height of 140""", the stalk to the first division is 35 ram long. The smallest specimen, which is 

 only divided once, is 6$ mm high. The species, as mentioned, is very slender, the stalk of the largest 

 specimen has only a diameter of 2 mm , and farther up the thickness is 1 — i'5 mi ". The lateral branches 

 do not reach more than i mm in length. The consistency is of the common firmness. The colour (in 

 spirit) is whitish yellow to light brownish; the coating layer of the stalk is always a little darker. 

 The surface is smooth, but on the part with branches it appears under the microscope to be shaggy 

 from the projecting chelae. No distinct dermal membrane was seen; outermost in the skeleton a dense 

 layer of spicules is found, and outside of this a thin layer of tissue, copiously provided with micro- 

 scleres. Oscula and pores were not observed. 



The skeleton. The skeleton of the axis consists of closely united, parallel needles. Through 

 the axis run a number of canals, which in the ramigerous part seem to be arranged in a more or less 

 ringlike way, and are separated by narrow parts of spicules, as also the fibres of the lateral branches, 

 where such are found, pass in between them. Lower down in the stalk the canals are not regularly- 

 arranged, so the separating spicula-parts are also here, when seen in transverse sections, irregularly 

 sinuous. Accordingly, the skeleton of the axis is by the canals divided into fibres or narrow, fibrelike 

 parts. Outmost a dense layer of spicules is found, which is most frequently rather easily loosened 

 on the stalk below the ramigerous part, while on this part such is not the case, and here where the 

 lateral branches are inserted, the needles of this layer do not exactly run in the direction of the longi- 

 tudinal axis. In the lower part of the stalk the axial skeleton is twisted in a spiral manner. The 

 skeleton of the lateral branches consists of bundles of spicules ; they are inserted between the spicules of 

 the axis in the common way, and reach to, or about to, the middle. The skeleton of the axis consists 

 ofstyli, among which in the outer layer of spicules shorter subtylostyli are intermingled; the skeleton of 



