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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXII. 



PROTANKYRA ALBATROSSI, new species. 



Plate LXXXI, figs. 1, l^f,- Plato LXXXII, figs. 4, Aa-c. 



Tentacles 12 (varying occasionally to 13 or 14), with 4 digits, the 2 

 terminal being longest, a series o,f three to six small "sensory cups" 

 on either side of tentacle between proximal digit and base. Two ventral 

 Polian vesicles. Madreporic canal, single, dorsal. Deposits: Anchors 

 with a rather long shaft, spiny handle and upward to nine teeth on 

 either arm. Anchor plates rather large, very variable, with two large 

 central holes and numerous smaller ones; edge uneven; occasionally an 

 incipient handle. Along the radii, in oral disk, and tentacles, man\' 

 irregular rod-shaped, C-shaped, O-shaped, and variously formed grains. 

 Color in life, translucent white, often with a pale lilac tinge. Length 

 of large specimen, 100 mm., slender. 



LocaUtle.'^.-'Ty^Q (Cat. No. 21227, U.S.N.M.) from Station 3840, 

 south coast of Molokai Island, 266 to 314 fathoms, light-brown mud, 

 sand, rocks; bottom temperature, 46 '. Taken also at the following 



stations: 



List of Stations. 



Ninety .specimens. 



Tentacles are usually 12, but specimens with 13 and 14 are occa- 

 sionally found, often from the same station as those with 12. The 

 digits are fairly constantly 4; only in a single case out of a number 

 examined did a tentacle have 5. iVlong- either side of the tentacle 

 between the proximal digit and the base is a series of from three to 

 six small pear-shaped })odies attached by the smaller end, about 0.2 to 

 0.25 mm. in length. They apparently correspond to the "ciliated 

 sucking disks" which Semper figures for Anapta gracilis. In the 

 present specimens they appear to be considerably contracted, and it is 

 not certain whether there are cilia present at the tip. The series is 

 not always very regular, the proximal body standing out of line in 

 many cases. 



The anchor plates are very variable in shape, and manj'^ are in dif- 

 ferent stages of development. Complete plates range from 0.2 to 



