68 
CALYCOSILVA CANTHARELLUS. 
simplex, var. nov. 
Plate 1, figs. 9-19, 25-29; Plate 2, figs. 1, 2, 4-6, 14, 16; Plate 3, figs. 6, 7; Plate 4, figs. 21, 22; Plate 
5, figs. 3, 6, 10, 16, 17; Plate 6, figs. 1-4, 22, 23; Plate 7, figs. 11, 15, 18. 
megonychia, var. nov. 
Plate 4, figs. 1-20; Plate 5, fig. 21; Plate 7, fig. 19. 
All the specimens of this species were trawled at Station 4651 off northern 
Peru, on 11 November, 1904; 5°41.7' S., 82°59.7' W. ; depth 4063 m. (2222 f.); 
they grew on sticky, fine, gray mud; the bottom-temperature was 35.4°. 
The complete specimen shows that the sponge is, in outer appearance, similar 
to the mushrooms of the genus Cantharellus, and to this the specific name refers. 
It possesses spirally twisted onychhexasters, which I name helonychhexasters. 
Such spicules have not been found in any of the other (more or less fragmentary) 
specimens. In some of the latter the average and the maximum size of the 
onychhexasters is considerably greater than in the others. On account of this 
and other differences between them I distinguish three varieties within this 
species : — var. helix, with helonychhexasters (the complete specimen) ; var. 
megonychia, without helonychhexasters, with larger onychhexasters (six frag- 
mentary specimens) ; and var. simplex, without helonychhexasters, with smaller 
onychhexasters (twenty-five more or less fragmentary specimens). Twenty- 
four of the specimens of var. simplex are identical and obviously parts of the 
body proper of the sponge. These are designated C. c. var. simplex (A). One 
corresponds to the basal part and the stalk of the complete specimen. This is 
designated C. c. var. simplex (B). 
Shape and size. The complete specimen of C. c. var. helix (Plate 6, fig. 18) 
appears as a horizontally expanded plate, from near the centre of the lower side 
of which a slender stalk arises. The stalk is 52 mm. long, nearly circular in 
transverse section, and at the lower end, where it was attached to the sea-bottom, 
4 mm. thick. It gradually thickens above and measures at its upper end, where 
it gradually passes into the body proper of the sponge, 7 mm. in transverse diame- 
ter. Its lower portion is markedly bent and has the appearance of having first 
grown somewhat obliquely and later vertically. The plate, which is to be con- 
sidered as the body proper of the sponge, is irregularly oval in outline and 
measures 68 by 92 mm. Its central part, to which the stalk is attached, is 6 mm. 
thick. Towards the margin it thins out. The plate is somewhat bent in an 
undulating manner and at one place strongly curved inwards. In the figure 
