98 



P0R1FERA. II. 



the common structure, in the principal axes it is enormously powerful. Spicula: Megasclera oxca o-jij 

 — o'S'o"""; microsclera of three tonus, anisancorm unguiferm with five teeth, sometimes with six teeth in 

 the larger end, 0-026 — o-oj./""", sigmata of two forms, large ones o-op — o- 12""", small ones, zuitk compressed 

 terminal parts, o'Off—O'Ojj" 



, in m 



This species is more robust than the other Clador/iiza-species, and it seems also to be the one 

 that may grow to the largest size. It may be described as a bush with few stems. To judge from a 

 basal part in hand it is attached below to a hard substratum with an irregular base formed by more 

 stems. From this base thicker stems arise, dividing immediately and continuing upward with irregular 

 ramifications, growing thinner as they rise. From the principal stems and their ramifications thinner, 

 often branched lateral branches issue again, but there is otherwise no definite difference between 

 stems and lateral branches. In a couple of fragments in hand a tendency to a bilateral arrangement 

 of the branches is seen in the outermost ramifications. Branchlets issue in the common way from 

 stems and branches; they issue all round and are close-set, but they show no circular arrangement. 

 They are broadest at the base, and are slightly conical outward. The stems and branches are less 

 cylindrical than in the preceding species, as the branchlets are somewhat coalesced at their base, which 

 is most frequently somewhat compressed, and branchlets that are placed above each other are then 

 connected by low keels. In the stems this feature may be very prominent, so that the branchlets are 

 arranged more or less in rows on keel-shaped parts, while the intervening parts are smooth without 

 branchlets; by this means the stems get an angular or winged appearance. At the ends of the 

 branches the branchlets often become short and close-set, and the ends of the branches are rounded 

 and sometimes slightly swollen. The layer of tissue on the axes is down on the stems rather 

 thin, but becomes thicker in the outer ramifications. The largest specimen in hand, which is broken 

 both above and below and only consists of the skeleton, has a height of 26o mm and a breadth at the 

 base of 30 mm , and divides here into two principal stems which immediately subdivide. The mentioned 

 basal part, which consists below of several interwoven stems, has in this place a breadth of 50 mra . As 

 before mentioned the stems taper evenly upwards in the ramifications. The branchlets have an average 

 length of towards 5 mm , they are a little more robust than in the preceding species, and have in the 

 middle a thickness of ca. 0'5 mm . The colour (in spirit) is yellow or yellowish white. The consistency 

 is firm on account of the strong skeleton; but in the upper branchings the sponge is rather flexible, 

 and the branchlets are very flexible. The layer of tissue coating the axes is soft and brittle. The 

 surface is smooth, and slightly projecting spicules are found only at the ends of the branchlets. The 

 outermost layer of the tissue is not differentiated as a distinct or removable dermal membrane. Oscula 

 and pores were not observed. In one of the specimens in hand of this sponge worm-tubes and Bryozoa 

 are sitting on branches that are denuded of tissue; as the other branches of the specimen are sound, 

 the branches in question must accordingly have been denuded of the tissue while the sponge was living. 



The skeleton consists in the stems and branches of strong polyspicular fibres. These fibres 

 compose by far the greatest part of the mass of the sponge, and attain an enormous thickness. At 

 the lower end of the mentioned largest specimen, which is probably broken off a little above the base, 

 the axis is 30""" thick, a little up on the thickest stem the thickness was measured to i8 mn \ and farther 



