464 REVISION' OF TITE AXINELLID/E, i., 



Preisumably owing to their having become closed — as a result 

 of the contraction undergone by the specimen — oscula are not 

 indicated; in life, tliey must, at any rate, have been of very small 

 size. The dermal pores, for the most part, have also disappeared: 

 but traces of them remain, sufficient to show that the}' are dis- 

 tril)ut(Hl singly as in T. diyitatm^ and its ^■arieties. 



Skplpfon. — The prepared skeleton, viewed in the gross (PI. xxiii., 

 fig. 10), is of a pale creamy-white colour, and shows a sharpl}'- 

 circumscribed, dense core-region, of diameter rare! v less than one- 

 third, and frequently exceeding one-half, the total diameter of 

 the branches. The extra-axial skeleton presents somewhat the 

 appeai'ance of fur, being composed apparently only of fine silky- 

 lo(jking* onlivardly-directrd (i.fi., radial) fibres; under the micro- 

 scope, however, the radial fibres are mostly found to be connected, 

 though as a rule only at .very distant and irregular inter\als, by 

 delicate transverse fibres, often in the form merely of single 

 spicules unensheathed by spongin. Even the component spicules 

 of the radial fibres are I'arely more than 4- or 5-serial, and the 

 spongin cementing them, seldom sufficient to form a visible 

 sheath, is usually so small in quantity as barely to be perceptible 

 even in stained sections of the skeleton. The main fibres of the 

 axial skeleton, save in the stalk and the basal portions of the 

 older bi-anches, are, for the most part, almost equally deficient in 

 spongin, Init the spicules composing them are less compact 1}- 

 arranged than in the radial fibres, and are all mostly somewhat 

 greater in number: they form, with the aid of numerous connect- 

 ing fibres and spicules, as well as by interunion among themselves, 

 a close and rather intricate meshwork, in whicli the course of 

 individual main fibres cannot be easily traced. 



Megascleres. — The megascleres (which are approximately the 

 same — though, on the average, perhaps not tjuite so slender — in 

 the stalk as in the branches) comprise a goodly proportion of 

 sharp-pointed oxea; but the great majority are intermediate forms 

 showing every stage of transition between oxea and strongyla; 

 moderately scarce styli also occur. The more sharply pointed 

 spicules are very often irregularly ended, sometimes mucronate. 



