LYMNORELLA MICULA. 239 
irregularly over the surface are small rosette-like groups of larger apertures 
about ‘5 mm. each, with in some cases short horizontal open furrows radiating 
from them. There are only traces of canals extending inwards from these 
larger apertures. The spicular fibres are from ‘1 to ‘15 mm. in thickness; in 
transverse section they appear as a labyrinthine reticulation, with the dark axial 
three-rayed spicules in single series in the centre of the fibres, and the outer 
portion crystalline as in the species previously described. Fragments of slender 
filiform spicules can be distinguished, but no tuning-fork spicules have as yet 
been met with. 
The examples of this species are rare, the largest specimen known, which is 
now in the Jermyn Street Museum, measures 115 mm. in breadth by 110 mm. in 
height. The mode of growth readily distinguishes this species; in its surface 
characters it more nearly resembles L. inclusa, but the fibres are closer and more 
delicate. 
Distribution.—Inferior Oolite. Pea-grit series, at Crickley Hill and Andovers- 
ford, near Cheltenham. (Coll. Mr. R. F. Tomes; Mr. HE. Wethered.) 
47, LyMNoRELLA micuLa, Hinde. Plate XVIII, figs. 5—5d. 
1884. Inozponia micuna, Hinde. Quart. Journ. Geol. Soc., vol. xl, p. 779, pl. 
xxxy, figs. 1, 1 a—d. 
Sponges small, occurring as rounded or irregular nodose and somewhat lobate 
masses, sometimes showing indications of overlapping zones of growth with 
marginal bands of dermal layer. The base is either rounded or concave, and 
enclosed in a dermal layer. Some of the specimens show a surface only of 
smooth fibres with irregular interspaces, and may perhaps be considered as simple 
sponges; in some of the lobate forms there are faint indications of centres from 
which some obscurely-marked, open furrows radiate, but there are no oscules or 
tubular canals. The skeletal fibres are coarse generally, and range from ‘14 to 
‘37 mm. in thickness. They consist of axial three- and perhaps four-rayed 
spicules, and a definite marginal border of slender filiform spicules, and also of 
tuning-fork spicules (Pl. XVIII, fig. 55). The dermal layer consists of three- 
rayed spicules of various dimensions. The rays of the larger spicules reach a 
length of -3 mm. by ‘05 mm. in thickness. Some of the tuning-fork spicules are 
very perfectly shown; in the one figured (PI. XVIII, fig. 5 c) the straight-paired, 
parallel rays are as long as the unpaired ray. The spicule is *25 mm. in length. 
_ The sponges range from small—perhaps incomplete—forms not more than 
2°5 mm. in thickness to rounded masses 32 mm. in diameter. In its mode of 
