190 ACTINl.E OF ALBATROSS EXPLORATIONS MCMURRICH. 



possess only coronal tubercles but have a ridged capituluni Avitli Hert- 

 wiji's PhflJia spiniffru m the new i^eiius CliifoiKoiflius. It is of course 

 a ([ucstiou as to whether the presence or absence of capitular ridjics is 

 worthy the ini]>ortance which this arrauj;ements;ives it; but it nuist be 

 recogni/ed that the classification of thv. Chondractininn' is. at ])resent 

 more a (piestion of convenience in identification than of i>hylo,uenetic re- 

 lationship, and that what may be trivial characters have been raised to 

 the elevation of generic distinctions. Thus, to judjic from Haddon's 

 definitions of the genera, the ]>rincipal feature wliich distinguishes 

 Chondractinia from Chitonavtis is that the tubercles in the latter ai'e 

 pointed, Avhile th(\v are mostly low and nodule like in the former. (See 

 appendix p. L'OO.) 



29. Chitonanthus pectinatus ( I Kit w i.n). 



riate XXXII, Fi<;s. !W-10l'. 



Svuouyra: rhellia pecthiata Hertwig (1882); rhcnia Kphii/era Hertwig (1888). 

 No. 703. Station 2780. feat. 53^^ 01' S. ; long. 73° 12' 30" AV. l>ept.li, 369 fathoms. 

 Three specimens. 



The three s])ecimens which repn'sent this s|)ecies have a very difterent 

 appearance from one another. Ont^ (PI. xwii, l^'ig. US), which may be 

 considered the most typical, is vseated upon a detached valve of a Lainel- 

 libraiich shell by a bioad, flat disk. Its column was much contracted 

 and thrown, to a certain extent, into folds. It measured2.l"" iu height 

 and 1.9'"' in diameter, and was covered with irregularly scattered tuber- 

 cles which were low and fiat near the base, but sharp and prominent 

 above, where they become more numerous. The upper tubercles owe 

 their sharpness to a strong development of cuticle over them, and it is 

 possible that in the lower ones this cuticular i)oint has been lost. 

 Though scattered irregularly over the column for the most part, yet 

 they show a tendency to arrange themselves above in twelve longitu- 

 dinal rows. 



The second specimen, the one which 1 chose lor detailed study, is 

 larger than the fiist, measuiing .■».5""' in height and .">"" in breadth. Its 

 base is broad and flat, like that of the first specimen, but had been de- 

 tached from its support, only i)articles 3f a shelly nature being attached 

 to it. The column is almost smooth and white in color, the brown cuti- 

 cle, which covered the first specimen, having disappeared, except in the 

 immediate neighborhood of the limbus. 1'he general smoothness of t lie 

 column is, however, relieved by a few nodule like elevations (PI. xxxil, 

 l"'ig. ',)!•), and some rarei', move iMomineiit nodules tipiietl with brown 

 cuticle. Toward llu' summit, howcNcr, one tinds twelve strong ridges, 

 each more or less broken into rows of tnluMcles and terminating above 

 in a strong tubercle tipped with a ]»it)miMent thickening of cuticle. 



The third specimen measured 2<"" in height and 2.5'''" in breadth, and 

 was seated upon the valve of a Lamellibranch shell. Like the second 

 specimen it was white in color, only a few isolated patches of cuticle 



