36 Mr. A. II. Clark on new Crinoids 



the lateral spines disappear and the median becomes slightly 

 more prominent, occurring as a small single submedian 

 tubercle directed obliquely forward ; all the dorsal processes 

 are small and inconspicuous. 



The arms are from twenty-five to thirty in number, and 

 about 50 mm. in length ; IIIBr series are always present on 

 some or all of the rays. 



Type Locality. 'Siboga^ Station No. 49 a ; Sapeh Strait, 

 between Sumbava and Komodo, Sunda Islands ; 69 metres. 



Decametra mylitta^ sp. n. 



This new form is nearest to D. mollis from Kurrachi,but 

 the cirri are slightly stouter, the majority of the segments 

 being twice as broad as long or even somewhat broader in- 

 stead of only slightly broader tlian long as in TJ. mollis, and 

 the proximal pinnules, while of about the same proportions, 

 are relatively longer and stouter and are composed of some- 

 what shorter segments. 



The centrodorsal is. discoidal, the flat dorsal pole being 

 1*5 mm. in diameter; the cirrus sockets are arranged in two 

 closely crowded alternating marginal rows. 



The cirri are XIX, 20-23, 10 mm. or 11 mm. long: the 

 cirrus segments are subequal in length and all short ; the 

 first is very short, the second slightly longer, the third and 

 following about twice as broad as long or slightly broader ; 

 the last three before the penultimate increase slightly in 

 length, so that the antepenultimate is about one-third broader 

 than long ; the earlier segments have the dorsal surface 

 swollen and distally truncated, so that the dorsal profile of 

 the cirrus is serrate ; after the first three segments the dorsal 

 profile becomes straighter, making a considerable angle with 

 the longitudinal axis of the cirrus, and the distal edge be- 

 comes straight, forming a very finely spinous trausverse 

 ridge, which, however, is not raised above the general 

 surface of the segments ; this transverse ridge becomes 

 gradually more and more marked, at the same time moving 

 more and more toward the centre of the dorsal surface ; on 

 the ninth segment it becomes median and begins to acquire 

 a slightly concave profile, and after the fourteenth it resolves 

 itself into two prominent, entirely distinct, tubercles situated 

 side by side, the distance between their two apices being 

 about equal to the distance from either apex to the outer 

 edge of the segment ; distally these two tubercles gradually 

 approach each other, and gradually move nearer the proximal 

 margin of the segments ; on the fourth segment before the 



