— 31 — 
Geodia? coronata n. sp. 
(Plate II fig. 6, 7, 8.) 
Very robust spicules with a conical] shaft, inflated at the 
upper end, and from thence gradually tapering to a point. 
Immediately on the inflated shoulder of the shaft, or with 
a very short intervening neck, are placed from 3 to 6 relatively 
very short, pointed rays, at a more or less open angle with 
the shaft. The shafts of these spicules are mostly straight, 
but sin’ one example the lower end is curved. The rays, both 
ofthe simple and compound forms are very equal in size, 
and the compound rays bifurcate so close to the head of 
the shaft, that, in many instances, they appear to spring from it 
independently. As in the previous species, one or all of 
the primary rays of a spicule may become bifurcated. The 
total length of a small spicule (fig. 8) is 2,25 mm.; width 
across the head 0,45 mm.; diameter of shaft 0,27 mm. The 
length of an average spicule is 4,05mm., the width of the 
rays 0,315mm.; and of. the shaft 0,45mm. These spicules 
are. somewhat rare. 
_ From the peculiar arrangement of the rays, I propose 
to name this spicule Geodia? coronata. Similar spicules are 
present in the Chalk of the North of Ireland (Wright: op. cit. 
Pio alk fies 3a,. rab). 
Geodia? Wrightii n. sp. 
(Plate II fig. 12). 
Robust simple trifid spicules with an elongated shaft 
gradually tapering from the summit to the pointed extremity, 
the arms straight and directed forwards at angles varying 
between 35° and 60° with the shaft. The shaft furnished 
with from 10 to 14 ring-shaped expansions, extending at 
regular intervals from each other, from the summit to two-thirds 
or three-fourths of its length, the lower portion of the shaft being 
smooth. Each of the arms has also 4 to 6 similar rings. In some of 
the smaller spicules the rings of the shafts and arms are by no 
