NO. 1820 RECENT CRINOIDS FROM PHILIPPINES CLARK 22/ 



Family THALASSOMETRID^ 



Genus THALASSOMETRA A. H. Clark 



THALASSOMETRA COMPRESSA (P. H. Carpenter) 



Station No. 5110; off Talin Point, west Luzon (14° N. lat.) ; 139 

 fathoms. 



Genus CHARITOMETRA A. H. Clark 



CHARITOMETRA SMITHI, new species 



This is a species of Charitonictra falhng in the division including 

 C. angusticalyx, C. incequalis, C. distincta, C. hrevipinna, and C. im- 

 hricata, species with the second division-series usually 4 (34-4) and 

 the third 2 (i-f-2), and with usually about thirty arms. The 

 division-series and lower arm joints are in very close apposition so 

 that the distichal pinnule is not visible exteriorly, as it is in C. dis- 

 tincta and C. imbricata {=^ granulifera of P. H. Carpenter, not of 

 Pourtales) ; the strong carination of the more distal cirrus joints and 

 the presence of an opposing spine, combined with the smooth and 

 evenly rounded division-series and arm bases distinguish it at once 

 from C. angusticalyx and C. hrevipinna, while the length of the prox- 

 imal and the shortness of the distal cirrus joints, the latter having 

 the distal dorsal edges so prominent as to appear almost spinous, 

 preclude any possibility of confusion with C. incequalis. It may be 

 described as follows : 



Centro-dorsal thick discoidal or short-columnar, the cirrus sockets 

 arranged in two rows and roughly in three irregular columns in each 

 radial area, though the middle column is sometimes lacking. 



Cirri xxvii-xxx, 19-22 (usually 20) ; first joint very short, second 

 about twice as broad as long, third nearly squarish, fourth slightly 

 longer than broad, fifth nearly half again as long as broad ; follow- 

 ing joints decreasing very gradually in length, the tenth and follow- 

 ing being about as long as their distal diameter; the joints after the 

 eighth or ninth becoming rounded carinate dorsally, soon developing 

 rather prominent rounded tubercles situated on the distal dorsal edge ; 

 opposing spine, though prominent, small, terminally situated, reach- 

 ing a height equal to about half the diameter of the penultimate 

 joint or rather less, its base occupying only the distal third of the 

 joint; terminal claw about as long as the penultimate joint, rather 

 stout and moderately curved. 



Disk completely covered with small plates ; side and covering 

 plates of arms and pinnules very well developed. 



