26 THE APODOUS HOLOTHUEIANS 



Protankyra duodactyla, sp. nov. 

 (Su'w, two + ^KTvXa (poetic plural), fingers; in reference to the number of digits.) 



Plate IV, Figs. 1-7. 



Tentacles 12, well expanded, eacli with only 2 digits. Calcareous ring nar- 

 row, 1 mm. high, the radial pieces slightly higher and perforated for passage of 

 the nerve. Cartilaginous ring wanting. Polian vessels only 2. Stone-canal 

 single, of moderate size. Genital glands long and branched. Body rather stout, 

 cylindrical. Anchors 360 ju. long, similar to those of inhcerens, though the base 

 is somewhat wider. Plates 300 1>. long, unlike those of any known synapta, per- 

 fectly flat, usually with no bow, and with smooth holes. Two holes are much 

 larger and more elongated than the others, and lie side by side, with the smaller 

 holes more or less sjTnmetrically arranged at the two ends of the plate. One 

 end usually has many more holes than the other, and no two of the plates are 

 exactly alike ; many seem to be only partly developed. Miliary granules want- 

 ing, but there are numerous branched rods and perforated plates in the tenta- 

 cles. Color, uniform gray. Length, 60 mm. Diameter, 8 mm. 



The specimen just described (type, Cat. No. 19,829, U. S. N. M.) was taken 

 at "Albatross" Station 2871, in 1,006 m., lai 46° 55' N., long. 125° 11' W., about 

 60 miles off Gray's Harbor, Washington. A second specimen, in very poor con- 

 dition, is in the collection, from lat. 54° 11' 30" N., long. 167° 25' W., 1,777 m. 

 In this specimen the plates are only 250 1^ long, and many of them have a 

 more or less incomplete bow on that end of the plate which has the more 

 numerous holes (fig. 5). The presence of only 2 digits allies this species to P. 

 bicornis (p. 101), but the plates are very different from those of that or any 

 other species. 



Anapta fallax Lampert. 



There are 2 incomplete specimens from off the southern coast of Chile, 

 "Albatross" Station 2784, lat. 48° 41' S., long. 74° 24' W., 350 m. Both are 

 anterior ends of small individuals, the oral discs being only 3 mm. in diameter. 

 Each has 12 tentacles with 7 or 9 digits. The minute elliptical rods are most 

 numerous along the radii, and the tentacles are richly supplied with slightly 

 curved rods, which are either smooth or rough. The color of these specimens is 

 pale yellowish brown. 



CniEmoTA DISCOLOR Eschscholtz. 



There are considerably more than 600 Chiridotas in the collection, which 

 almost defy classification, for though the largest specimens are easily separated 

 from the smallest, not only by size, but by color and general appearance, there 

 are almost all possible intergradations between the extremes. The largest 

 specimens are all from Alaska or Siberia, and are distinctly gray or creamy 



