254 THE VOYAGE OF H.M.S. CHALLENGER. 



The second joint above the radial axillary, whether brachial or distichal, has a pinnule 

 about 10 nam. long, composed of some thirty elongated joints, the basal ones being rather 

 stout. The next few pinnules are much shorter and less stout at the base, with fewer 

 joints, and then' successors increase again, becoming long and filiform in the outer parts 

 of the arms. 



Disk naked and much incised ; the rays and the lowest pinnules somewhat webbed 

 by perisome ; sacculi abundant on the disk, arms, and pinnules. 



Colour in spirit, — the skeleton a very light brown, and the perisome darker. 



Disk 9 mm.; spread about 9 cm. 



Locality. — Station 192, September 26, 1874, near the Ki Islands; lat. 5° 49' 15" S., 

 long. 132° 14' 15" E.; 140 fathoms; blue mud. One specimen. 



Remarks. — This type is unfortunately represented only by a single and much- 

 mutilated individual, the disk of which bears the cysts of Myzostoma inflator, von Graff. 

 It may be readily distinguished, however, from the other members of the group by the 

 abundance of long and spiny cirri, and by the complete freedom of the rays, the second 

 radials not coming into lateral contact at all. 



One of the distichal series is only two-jointed, as shown on the right of the figure 

 (PL XL V. fig. 4); while in that on the left side the two elements of the axillary have 

 almost the appearance of being articulated and not united by syzygy. If this be really 

 the case, it is a somewhat anomalous condition, especially as the lower joint, the normal 

 " hypozygal," bears no pinnule. 



2. Antedon anceps, n. sp. (PL XXXV. figs. 1-3). 

 Specific formula — A. ( 3 ). -r-. 



Centro-dorsal a low convex disk with about twenty cirri on its sides. These have 

 twenty-five to thirty-five tolerably uniform joints, few of which are longer than wide, 

 the later ones being slightly carinate. 



First radials partially visible ; the second short and partly united, forming a more 

 or less distinct tubercle at the middle of their junction with the widely pentagonal 

 axillaries. Ten to fourteen arms, distichal series being sometimes absent altogether ; 

 when present, they consist of three joints, the axillary with a syzygy. The arms have 

 about one hundred and fifty joints, the earlier ones triangular and much wider than 

 long, their successors becoming more quadrate and finally almost oblong, with a slight 

 tendency to overlap. A syzygy in the third, and then between the eighth and twelfth 

 brachials, with others at intervals of two to nine, usually four to seven, joints. The 

 first pinnule, whether distichal or brachial, is considerably smaller than its successor on 



