102 
Case and 
Column of 
Drawers. 

FC 
Gb9 
FC 
Gbi 
Reference to McCoy’s 
Synopsis: and Figures of Genera. 
p. 47. 
G. ludensis, p. 4. 
SILURIAN. 
Names and References; Observations, &c. 

Ptilodictya, Goldf. Petref. Germanica. Flat 
plates, with the cells very regularly ar- 
ranged on both sides of them. The species 
are often branched, once or twice, but al- 
ways in one plane. The genus is world-wide 
in Cambrian and Silurian, and very nume- 
rous in species. 
Ptilodictya lanceolata, Goldf. (Pet. Ger. t. 37, 
fig. 2) Siluria, 2nd ed. Foss. 49, fig. 6, pl. 41, 
fig. 11. Often attains great size, ten inches; 
easily breaks along the centre plate. 
Ptilodictya scalpellum, Lonsd. (Siluria, 2nd ed. 
Foss. 50, pl. 41, fig. 25). Slightly branched 
only: but leading away from the compound 
branched and explanate species of the Cam- 
brian to the simple P. lanceolata. Such spe- 
cies as the present would be included in 
Prof. Hall’s unnecessary genus Stictopora. 
Polypora or Hornera crassa, Lonsd. (Siluria, 
2nd ed. Foss. 49, fig. 1, pl. 41, fig. 13). Hor- 
nera only differs from Polypora (Devonian 
and Carboniferous) by wanting the connect- 
ing bars. 
HYDROZOA? or POLYZOA. 
The Graptolites are (I think not rightly) gene- 
rally now referred to the Hydroid Polypes. 
I prefer the analogy with such Bryozoa as 
Defrancia. 
Graptolites priodon, Bronn (G. ludensis) (Si- 
luria, 2nd ed. pl. 12, fig. 1, Foss. 11, fig. 3). 
See remarks on this common Northern fossil 
in the Cambrian lists. It is extremely com- 
mon at the base of the Wenlock in France 
and Bohemia. 



Numbers and Localities. 
Aymestry (Haven), b. 658, 
Dudley, F. C.; b. 661, Led- 
bury. 
b. 659, Dudley, F. C. 
b. 660, Dudley, F.C. 
a. 468, S. of the Dee, Llan- 
gollen; b. 662, Smithfield ; 
b. 663, Cwmbach, Builth; 
also b. 664, bed of Wye, 
Builth; b. 665, Cwm, W. 
of Cefn Grugos, Llanfyllin ; 
b. 666, Llanfair; b. 667, 
Ffyrnwy, Montgomery- 
shire, 
