REPORT ON THE CRINOIDEA. Ill 



the seventh to tenth are longer than wide. The following ones are shorter and develop 

 a well-marked spine. 



First radials scarcely visible ; the next two short and convex, with occasional traces 

 of a median ridge, especially in young individuals. Axillaries short and widely 

 hexagonal, projecting backwards into the second radials. Both joints as well as the first 

 brachials have straight edges and flattened sides. The inner faces of the second and the 

 hypozygals of the third brachials are also slightly flattened. 



Ten arms ; the lower joints triangular or quadrate, rather longer than wide ; the 

 distal ones laterally compressed and overlapping so as to become carinate. 



A syzygy in the third brachial ; the next between the twelfth and twenty-fifth 

 (usually about the fifteenth), and others at intervals of from one to fifteen, usually three 

 or four joints. 



The first pinnule, which is much larger than the second, consists of about a dozen 

 joints. The first six are wide and thick, with their outer sides somewhat flattened, and 

 the third to the fifth have their inner edges produced into expanded processes which are 

 slightly folded upwards. The next three or four pinnules on either side are quite small 

 and the length gradually increases, the later pinnules becoming styliform, with elongated 

 joints. In some arms the first two joints of the distal pinnules are rather expanded and 

 trapezoidal, but in others they are not specially modified. 



Disk and brachial ambulacra well plated. Side plates and covering plates of the 

 pinnule-ambulacra generally well differentiated. Sacculi largely developed in some 

 pinnules and altogether absent in others. 



Colour in spirit, — light brownish-white. 



Disk 6 mm.; spread probably 16 cm. 



Localities. — Station 170a, July 14, 1874 ; near the Kermadec Islands ; lat. 29° 45' S., 

 long. 178° 11' W.; 630 fathoms; volcanic mud; bottom temperature, 39°'5 F. Five 

 specimens, one much mutilated, and another with cysts of Myzostoma murrayi. 



Station 175, August 12, 1874 ; near Kandavu, Fiji; lat. 19° 2' S., long. 177° 10' E.; 

 1350 fathoms; Globigerina ooze ; bottom temperature, 36° F. One imperfect specimen 

 with a cyst of Myzostoma murrayi. 



Remarks. — This is a singular species which unites three forms that I was at first 

 inclined to consider as distinct. Like Antedon htsitanica it is an exclusively abyssal 

 type, ranging down from 630 to 1350 fathoms, and individuals from each depth were 

 infested with the cysts of Myzostoma murrayi, von Graff (PI. XIX. fig. 2). 



The second radials are relatively longer than in Antedon lusitanica and more 

 distinctly incised by the axillaries, which are hexagonal rather than pentagonal as in that 

 species (PL XL fig. 5 ; PI. XIX. fig. 1 ; PI. XX. fig. 1); while in the younger individuals 

 both the second and the axillary radials show distinct indications of a median ridge like 



