LOWER AND UPPER GREENSAND OF THE SOUTH OF ENGLAND. 451 
Figs. 15, 15a. Tethyopsis Haldonensis, Carter. Zone spicules.—Blackdown, Haidon. 
X 40 diameters. 
i Figs. 16, 16a. Geodites Haldonems, Carter. “ Anchor” spicules, shafts incomplete. 
—Haidon, Penzlewood. X 40 diameters. 
Figs. 17, \7a-h Small trifid spicules of different species. Figs. 17, 17a, b, young 
spicules of Geodites. X 60 diameters. Figs. 17c, d, e, allied to Pacha¬ 
strella. Figs. 17g, h, i, spicules replaced by glauconite. Fig. 17lc, dermal 
spicule of lithistid. X 60 diameters.—Blackdown, Warminster, Merst- 
ham, Yentnor. 
PLATE 43. 
Figs. 1 , 1 a-d. Tethyopsis Haldonensis, Carter. —Blackdown. X 40 diameters. 
Figs. 2, 2 a-f. Geodites. Globate and globostellate spicules of the dermal layer of 
various species.—Haslemere, Blackdown, near Warminster. X 80 dia¬ 
meters. 
Fig. 3. Stellettites callodiscus, Carter. Spicule of the dermal layer.—Near War¬ 
minster. X 80 diameters. 
Figs. 4, 4 a-i. Pachastrella Haldonensis, Carter. Four-rayed spicules of the skeleton. 
Blackdown; near Warminster, Merstham. Fig. 4a. X 60 diameters ; the 
others X 40 diameters. 
Figs. 5, 5a, b. Pachastrella Carteri. —Haslemere, Blackdown, Merstham. X 40 dia¬ 
meters. 
Figs. 6, 6a, Pachastrella quadriradiata, Carter. —Blackdown, near Warminster. 
X 80 diameters. 
Figs. 7, 7 ci-z. Doryderma. Spicules of various forms belonging to the body and stem 
of different species of this and allied genera of the megamorina family of 
lithistid8e.—Haslemere, Blackdown, Haidon, near Warminster, Merstham. 
X 40 diameters. 
PLATE 44. 
Figs. 1-14. Various forms of spicules of the dermal layer, probably belonging to 
different species of tetracladine lithistid®, of the genera Siphonia, Hal- 
lirhoa, Ragadinia, See. —From Haslemere, Blackdown, Haidon, near War¬ 
minster, Merstham. All drawn by means of the camera lucida to the 
same scale of 60 diameters. 
