CALYCOSILVA CANTHARELLUS. 
91 
C. c. var. C. c. var. C. c. var. 
helix simplex megonychia 
Rectangularly bent diactine 
megascleres present absent absent 
Large, slender-rayed triactines 
with two rays ina straight line b me 
and the third arising vertically | “ pBent Buseut present 
from this 
Amphiox, diactine hexactine- 
dorivates absent present absent 
domnial distal ray distal ray distal ray 
Body-pinules 120-270 uw long 100-240 uw long 100-180 » long 
gastral distal ray distal ray distal ray 
120-270 uw long 100-240 uw long 100-195 yw long 
erchh et 39-88 yu 48-106 pu 80-130 p 
SS aie in diameter in diameter 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! attaches little systematic importance to the presence 
or absence of hypogastral pentactines and accordingly proposes to unite the 
1T. Ijima. Studies on the Hexactinellida. III. Journ. Coll. sci. Tokyo, 1903, 18, p. 96. 
