84 
CALYCOSILVA CANTHARELLUS. 
and size; the number of them on each of the six main-rays is, however, by no 
means always the same. The end-rays are 1.5-2 n thick at the base, and arise 
steeply, sometimes at nearly right angles, from the main-rays. Farther on 
they curve inward, towards the continuation of the axis of the main-ray to which 
they belong. Distally this curvature rapidly decreases and the end-part is 
for a smaller or greater, usually a very considerable length, either quite straight 
or only slightly curved, or irregularly bent like an oak-branch and knotty in 
appearance. Onychhexasters with end-rays thus bent have been chiefly found 
in C. c. var. megonychia (Plate 4 , figs. 2-4, 14, 17). In all regular onychhexasters, 
whether large or small, the centrum, the main-rays, and the proximal parts of the 
end-rays are nearly identical in shape and have the dimensions given above; the 
great differences in these hexasters observed are entirely due to differences 
in the degree of longitudinal development of the distal straight end-parts of 
the end-rays. In the smallest onychhexasters observed (Plate 3 , fig. 21) this 
distal straight part is quite insignificant and hardly distinguishable. The 
larger the onychhexaster is, the longer and the more conspicuous does this part 
of the end-ray become (Plate 3 , figs. 22-27; Plate 4 , figs. 2-7). The end-rays 
are cylindroconic, attenuated distally. This attenuation is slight and very 
much the same in all end-rays, however long they may be. The consequence 
of this is that the thickness of their distal ends is in inverse proportion to the 
length of the -end-rays; greatest in the shortest, and smallest in the longest. 
In the small onychhexasters, 39-45 n in diameter, of C. c. var. helix, the end-rays 
are 15-18 /z long and 1-1.8 m thick at the end; in the largest onychhexasters, 
80-88 id in diameter, of the same variety the end-rays are 34-41 m long and only 
0.8-1 /d thick at the end. In the larger onychhexasters of C. c. vars. simplex 
and megonychia the same inverse relation between the length and terminal thick- 
ness of the end-rays is observed. The angles between the chords of end-rays 
arising opposite each other from the same main-ray are correlated and in inverse 
proportion to the size of the spicule and the length of the end-rays. In the small 
onychhexasters, 39-45 n in diameter, of C. c. var. helix, these angles are 70°-90°; 
in the large ones, 80-88 m in diameter, of the same variety 59°-77°. 
The end-rays bear numerous small recurved spines along their length 
(Plate 3 , fig. 28; Plate 4 , figs. 9, 10, 16) and one to five large spines at the end. 
The former are largest and most conspicuous in the smallest onychhexasters 
(Plate 3, fig. 22) ; in the large onychhexasters they are smaller. Their size is, on 
the whole, in inverse proportion to the length of the end-rays and the size of 
the whole spicule. In the smallest onychhexasters the terminal spines are 2-3 n 
