MUSEUM OF COMPARATIVE ZOOLOGY. 79 



Description of an Individual (Royal Sound). — Diameter of disk 1 1 mm. 

 Length of arm 45 mm. "Width of arm 2.5 mm. Mouth-papilloD short, bhmt, 

 close-set, four or five on each side, and two longer at apex of jaw. Mouth- 

 shield pentagonal, with a blunt angle inward, outer edge curved, lateral sides 

 notched ; length to breadth, 2.3 : 2. Side mouth-shields extending along inner 

 angle of mouth-sliield, narrow, of about even width, meeting within. First 

 under arm-plate very large, broader than long, transverse oval in shape ; next 

 three plates wider without than within, their sides straight, except the outer, 

 which is curved ; the rest are triangular, with outer edge curved, and an angle 

 within. Side arm-plates short, slightly swollen, just meeting below, beyond 

 the disk ; widely separated above by the upper arm-plates, wliich are large, 

 arched, much broader than long, wider without than within, with outer side 

 curved and inner side re-enteringly curved. The upper surface of disk has 

 numerous rounded, much swollen plates, closely soldered together, with a clus- 

 ter of six primaries in the centre separated by one or two rows of smaller 

 plates ; outside this cluster in each interbrachial space is another large rounded 

 plate. Radial shields longer than broad, much rounded, the inner end slightly 

 smaller than outer, their inner ends widely separated by a large rounded tri- 

 angular plate within and smaller scales without ; length to breadth 2 : 1.5. 

 Interbrachial space below evenly covered by small thick scales. The genital 

 scale is nearly or quite covered, except at its outer portion, whose free edge 

 carries a row of very fine saw-like papillaj, which become a little longer above, 

 where they make the arm-comb. Three small blunt arm-spines, equally 

 spaced, and standing low on the outer edge of side arm-plate. The pores of 

 the mouth-tentacles have four or five close-set, small, tooth-like scales on each 

 side ; the second and third set have four or five on the interbrachial side, and 

 three on the brachial ; beyond this they diminish till a short distance beyond 

 the disk, where there is on the inner side a small scale, similar to and con- 

 tinuous with the arm-spines, and on the outer side a little ridge. Color in 

 alcohol, light gray, 



Mr. Smith, who kindly compared a " Challenger " specimen with his originals, 

 reports that the latter are smaller, and differ from the former in having 

 disk-scales coarser, radial shields that converge and touch each other, upper 

 arm-plates narrower inward, etc. As these differences may depend on age, I 

 have retained the name with a qxier}% 



Royal Sound, Kerguelen Islands, 25 -28 fathoms, 12 + specimens. Balfour 

 Bay, Kerguelen Islands, 20 - 60 fathoms, 2 specimens. Off Christmas Harbor, 

 Kerguelen Islands, 120 fathoms, 1 specimen. 



Ophioglypha ambigua sp. nov. 



Plate II. Figrs. 47, 48. 



Special Marks. — Four short, blunt, peg-like arm-spines, three together, 

 low down, and one higher up. Papilla) of arm-comb short, close-set, and 

 squarish. Disk-scales of moderate size, thick and swollen. Very small, narrow 

 side mouth-shields. 



