CALYCOSILVA CANTHARELLUS. 
91 
C. c. var. 
helix 
C. c. var. 
simplex 
C. c. var. 
megonychia 
Rectangularly bent diactine 
megascleres 
present 
absent 
absent 
Large, slender-rayed triactines 
with two rays in a straight line 
and the third arising vertically 
from this 
absent 
absent 
present 
Amphiox, diactine hexactine- 
derivates 
absent 
present 
absent 
Body-pinules 
dermal 
distal ray 
120-270 n long 
distal ray 
100-240 ju long 
distal ray 
100-180 ju long 
gastral 
distal ray 
120-270 fj. long 
distal ray 
100-240 n long 
distal ray 
100-195 m long 
Onychhexasters 
39-88 ij. 
in diameter 
48-106 m 
in diameter 
80-130 M 
in diameter 
Oxyhexasters 
present 
absent 
present 
Helonychhexasters 
present 
absent 
absent 
F. E. Schulze differs from it by its shape and by some of its spicules. In Aulascus 
johnstoni all the pinules have a properly developed proximal ray, and discohex- 
asters and discohexaster-derivate discohexactines occur. In Calycosilva. can- 
tharellus many pinules have a reduced proximal ray, and discohexasters and 
discohexactines are absent. Also the plumicomes are somewhat different. 
Among the above mentioned related forms without pentactine hypogastralia, 
Calycosoma gracile F. E. Schulze, which is not very different in shape and has 
very similar onychhexasters and plumicomes, appears to be most closely allied 
to Calycosilva cantharellus. The differences between the latter and the most 
similar of the allied forms {Aulascus johnstoni and Calycosoma gracile), let alone 
the others, are so considerable as to necessitate the establishment of a new 
species for its reception. 
Whilst I experienced no difficulty in coming to this decision about the estab- 
lishment of a new species, I found it exceedingly difficult to decide whether this 
new species should be assigned to one of the three genera mentioned, and if so, 
to which one. Ijima 1 attaches little systematic importance to the presence 
or absence of hypogastral pen tac tines and accordingly proposes to unite the 
1 1. Ijima. Studies on the Hexaetinellida. III. Journ. Coll. sci. Tokyo, 1903, 18, p. 96. 
