Mr. F. J. Bell on two new Species of Asteroidea. 333 
EXPLANATION OF THE ILLUSTRATIONS. 
PrarE X1V. 
Fg. 18. Contents of the Altmiihl-valley diluvium. a, spiniferous spi- 
cule, characteristic average largest size; 6, the same, smallest 
size ; ¢, vermicular spicule ; 4, birotulate spicule; all drawn to 
the same scale, viz. 1-48th to 1-G000th inch, to show their sizes 
relatively. d, group or aggregated mass of vermicular spicules ; 
e, various forms of the vermicular spicule; scale 1-24th to 1- 
6000th inch. f, vermicular spicule, more magnified, to show 
trace of a central canal. g, the smaller size of spiniferous spi- 
cule (“6”), more magnified, to show the form and recurvature of 
the spines in the smaller spicules generally; 7, the birotulate “ h,” 
more magnified, to show the form of the shaft and arms; k, 
pollen-grain of Conifer; J, tetraspore of acotyledonous plant. 
The two latter on the scale of 1-24th to 1-GQ00th inch, 
XXX VII.—Deseriptions of two new Species of Asteroidea tn 
the Collection of the British Museum. By F. Jerrrey 
BELL, M.A. 
THE Asterias now to be described was not satisfactorily re- 
cognized as an undescribed form at the time when I gave to 
the Zoological Society some account of the genus to which it 
belongs*. The Culcita has been long known to me as a new 
form, but I have refrained from publishing any account of it, 
in the hope that it might soon be possible to make a revision 
of the group to which it belongs. As it is now, however, ex- 
hibited in the new galleries of the Zoological Department at 
South Kensington, the student will probably tind it con- 
venient to have an account of it. 
Asterias nautarum. 
General formula, 2 aa’. 
Arms five, do not begin to taper till the last third of their 
length, broadest at a short distance from their base; two 
rows of adambulacral spines; madreporic plate anechino- 
placid, obscure, not far from the margin of the disk. Spines 
autacanthid, very blunt on abactinal surface. ‘The abactinal 
surface presents an appearance of very close packing, as there 
are on it three rows of autacanthid spines ; those of the outer- 
most are very fairly developed. ‘This last-mentioned row 
bounds the lower, while a row as well marked bounds the 
* P.Z.S. 1881, p. 492. 
Ann. & Mag. N. Hist. Ser. 5. Vol. xii. 24 
