MUSEUM OF COMPARATIVE ZOOLOGY. 49 



4 mm. Fifteen small, close-set mouth-papillae to each angle, whereof the two 

 or three outer ones on each side are flat, rounded, and larger than the rest, 

 which are pointed ; there are two just under the teeth, and sometimes two 

 supplementary below and outside these. Mouth-shields long heart-shaped, with 

 a rounded angle within ; length to breadth 3 : 2.2. Sometimes a rudimentary 

 supplementary piece may be seen, just outside. Side mouth-shields three- 

 cornered and small, occupying only the outer corners of the mouth-shield. 

 Under arm-plates about as wide as long, bounded without by a curve, within 

 by a truncated angle, and laterally by re-entering curves. Side arm-plates 

 short, with rounded edges, meeting neither above nor below. Upper arm- 

 plates broad, highly arched, closely overlapping, with outer and inner edges 

 nearly straight. Disk flat and angular, closely and evenly covered with very 

 fine granules, 7 or 8 in the length of 1 mm., except the radial shields and one or 

 more plates along the margin. Radial shields egg-shaped, longer than broad, 

 with outer and inner ends much rounded ; length to breadth 3.7 : 2. Lower 

 interbrachial space covered by same granulation as above, extending even to 

 the mouth-angle, but not on mouth-shields. Genital opening long, extending 

 from mouth-shield to margin of disk. Three short, small, blunt arm-spines 

 standing low on the side arm-plate, and about half as long as a joint. One 

 round tentacle-scale. Color in alcohol white. 



Station 191, 800 fathoms, 1 specimen. 



This species stands as near P. stellata as to any ; there are, however, no pores 

 between the under arm-plates, and but three short arm-spines. The only oc- 

 casional presence of rudimentary supplementary mouth-shields points once 

 more to the very close connection between Ophiopeza and Pectinura. 



Pectinura maculata Vll. 



Pectinura maculata. Proc. Bost. Soc. N. H., XII., 1869, p. 388. 

 Queen Charlotte's Sound, Ncav Zealand, 10 fathoms, 5 specimens. 



Pectinura rigida Lym. 



Pectinura rigida. Bull. Mus. Comp. Zodl., III. 10, 1874, p. 224. 

 Fiji Islands, 2 specimens. 



Pectinura stellata Ltk. 



Pectinura stellata. Addit. ad Hist. Oph., Pt. III., 1869, p. 33. 

 Station 208, 18 fathoms, 1 specimen. 



Pectinura gorgonia Ltk. 



Pectinura gorgonia. Addit. ad Hist. Oph., Pt. III., 1869, p. 33. 

 Fiji Islands, 1 specimen. 



VOL. VI. NO. 2. 4 



