228 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 48. 



sukuri, end-plates are present in pedicels in most cases. They are 

 rudimentary and are irregularly perforated, measuring at most 0.1 

 mm. in diameter. Besides the smooth, latticed plates in perianal 

 region there are scattered smaller spinose bodies. 



Habitat. — Moluccas and Timor (Sluiter, 1901) ; Sagami Sea (Mit- 

 sukuri, 1912); Suruga Bay; off Kii, Honshu. 



13. PSEUDOSTICHOPUS ALEUTIANUS, new species. 



Plate 8, figs. ba-c. 



Station 4768. Seventy-six specimens. 

 Station 4774. Three specimens. 



Body flat and elongated, 73 mm. long, rounded at both extremi- 

 ties. Mouth ventral, anus lodged in a vertical pygal furrow. Body 

 is thickly coated all over with sponge spicules and foraminiferan 

 shells. Tentacles 20. Pedicels of ventrolateral ambulacra largest, 

 about 1 mm. long, forming a double row. Scattered smaller papillae 

 ( ?) forming a double row along each dorsal ambulacrum. Scattered 

 on the midventral ambulacrum, as well as on all interambulacra, are 

 found very minute pedicels. X-shaped spicules present in wall of 

 genital tubes, as in Ps. occultatus v. Marenzeller (pi. 8, fig. 5a). They 

 vary in size from 60 to 150/i. Around the anus are thinly scattered, 

 irregular, X-shaped spicules (fig. 5b) and also irregularly rod-shaped 

 ones (fig. 5c) . Their length varies from 80 to 200/z. Larger pedicels 

 have end-plates attaining the diameter of 80/£. Supporting rods of 

 tentacles slender and bent, with low processes and often siitlike 

 perforations. No deposits whatever are found in general perisome 

 nor in respiratory trees. Calcareous ring similar to that of Ps. 

 trachus. Polian vesicle single. Genital tubes not divided, in two 

 tufts. Respiratory trees two. 



The species differs from Ps. occultatus only in the absence of spicules 

 from respiratory trees and in the character of the deposits in perianal 

 region. 



Habitat. — Aleutian Islands. 



Type.— Cat. No. 34147, U.S.N.M. 



14. PSEUDOSTICHOPUS MOLPADIOIDES, new species. 



Plate 8, figs. 6a-c. 



Station 4982. Eight specimens. 

 Body cylindrical, not flattened, rapidly tapering at both extremi- 

 ties, measuring 52 mm. in length, 25 mm. in breadth, and 20 mm. in 

 height. Mouth terminal but directed ventrad, anus lodged in a 

 rather inconspicuous vertical furrow. Color dirty pale brown, sur- 

 face being covered all over with sand and foraminiferan shells, while 

 sponge needles are very few. Tentacles 20. Small pedicels also 



