NOTES. 267 
wards in the fish. It was altogether, therefore, an armature of 
defence, and not partly of offence, as hinted at in the text. Of this 
Mr. Miller had long been quite aware, and, in consequence, had 
expressed himself approvingly of the restoration figured in Plate x. 
An Arbroath specimen, in the possession of Mr. Powrie of Res- 
wallie, which shows the head in profile, has the cephalic shield 
bent round in the manner described. In the large majority of in- 
stances, however, the fish being found lying on its belly, the curva- 
ture of the shield has yielded to the pressure of the overlying stone, 
and the appearance of the head is consequently that of a perfectly 
flat crescent, as represented in Plate xiii. fig. 1. 
NOTE G, Paces 129 anv 137,—‘' Middle Empire.” 
Here, and elsewhere in these pages, the Forfarshire gray beds 
are spoken of as constituting the middle portion of the formation. 
BALRUDDERY SPINES. In “ The Testimony of the Rocks,” 
mem ON remarks, that “the evidence on the 
; point is certainly not so conclusive 
as I deemed it fifteen years ago” (p. 
452); and again (p. 455), “ It must, 
however, be stated, on the other 
hand, that the crustaceans of the 
gray tilestones of Forfar and Kin- 
cardine not a little resemble those of 
the upper Silurian and red tilestone 
beds of England; and that, judging 
from the ichthyodorulites found in 
both, their fishes must have been at 
least generically allied. The crusta- 
ceans of the upper Silurian of Lesma- 
hagow, too, seem certainly much akin 
to those of the Forfarshire tilestones.” 
The spines figured in the accompany- 
ing cut, when compared with those in Sir R. Murchison’s “ Siluria,” 
may help the scientific reader to determine the question. 
ADDITIONAL Note, By Rey. W. 8. Symonps. — In Worcester- 
eye however, pages 452-455, Mr. Miller 
