CLARK: PUGET SOUND ECHINODERMS. 
335 
many scattered pedicels on the spaces between. On the dorsal surface the rows 
along the ambulacra are less distinct, while the scattered pedicels are very few 
(fig. 21). Pedicels short, with few supporting rods in the walls. Tentacles 10, 
their relative size doubtful. In one specimen, in which they are most easily 
examined, the four dorsal ones are long and slender (4-5 mm.), while the other 
six are short and stumpy (2 mm.). But this peculiar arrangement may be 
wholly due to the manner and degree of contraction. The genital glands are 
well developed and consist of numerous, long (30 mm.), unbranched filaments. 
The respiratory trees (fig. 28) are very noticeable on account of the short 
branches, somewhat enlarged at the tips. These tips, in the specimens before 
me, are brown, while the rest of the tree is yellow, so that they are very conspic¬ 
uous. The muscles and digestive system show no unusual features. Stone- 
canal small and single. Polian vessel one or none. Calcareous ring (fig. 22) 
very small and delicate, not one third the size of that of C. chronhjelmi. Radial 
pieces broad, deeply notched behind, but with no long posterior prolongations. 
Interradial pieces broad, but with a long, narrow, anterior prolongation. Tenta¬ 
cles with large, broad, supporting rods (fig. 23). Pedicels with a few, peculiar, 
curved, supporting rods, bearing two projections on the convex side; the rod 
with from one to several holes in each end (fig. 24). In the body wall numer¬ 
ous, thick, knobbed plates or buttons, in all stages of development; most of 
them are nearly elliptical or even spherical, but others are more flattened. The 
simplest ones (fig. 25) are small, thick plates with four symetrically placed holes; 
others, somewhat larger, are very much knobbed; while in the great majority 
(fig. 26) the knobs have so fused into ridges and overgrown the plate that the 
holes are quite small and irregularly scattered. There seem to be no other 
deposits in the body wall. Color pale grayish brown; pedicels brown. Length 
from 10 to 40 mm.; the largest, 12 mm. in diameter. 
There are seven specimens of this little liolotlmrian, but there are 
no data to tell us anything of its habits or habitat. The speci¬ 
mens are all very much contracted, so that it is not possible to deter¬ 
mine exactly the proportions of the tentacles nor the size of the 
pedicels. In general appearance, arrangement of the pedicels, and 
shape of the calcareous ring, this species resembles C. vegae Theel; 
but it differs very markedly from that form, in the calcareous de¬ 
posits. Indeed it differs in that particular from all the forms known 
from the eastern Pacific, and does not seem to be closely allied to 
any known Cucumaria. The name lubrica has been selected for 
this species on account of the unusual smoothness of the surface of 
the body. 
Psolus chitonoides sp. nov. Plate 3, figs. 5 and 6. Plate 4 
figs. 6-10. 
This very well-characterized form is represented in the collection by nine¬ 
teen specimens, ranging in size from 10 X 14 mm. to 63 X 44. They are much 
