378 Proceedings of the Royal Physical Society. 
Coccosteus magnus, Traquair. 
[Plate X., Fig. 1.] 
Extinct Verteb. Moray Firth Area, p. 258, pl. vi., fig. 10 (anterior 
median ventral plate). 
In addition to the anterior median ventral plate of this 
species, figured in my previous memoir, I now give a drawing 
of a median dorsal plate, which was sent to me some time 
ago by Mr Taylor, and which is now in the Museum of 
Science and Art. Of course, I presume it to belong to the 
same species, as no other is known from the quarries in 
question (Kingsteps). 
The plate measures 4} inches in length and 22 inches in 
greatest breadth, and its contour is clearly shown, though, 
unfortunately, a large piece has been broken away from the 
right side in front. The greater part of the bone, showing 
the external sculptured surface, remains in situ, and the close 
tuberculation is proportionally finer, especially in the centre 
of the plate, than is usually the case in C. decipiens, 
Ag., of the Orcadian series. The sensory groove, like 
a V with backwardly directed rounded angle, is seen 
in the same position as that in which it occurs in the 
last-named species. 
FISHES FROM THE ALVES AND ELGIN BEps. 
Psammosteus Taylori, Traquair. 
[Plate XI., Fig. 5.] 
Ann. Scot. Nat. Hist., Oct. 1894, p. 225; Ext. Verteb. Moray Firth 
Area, pp. 260-263, pl. vi., figs. 1-3. 
Since I wrote my previous descriptions, more satisfactory 
examples of the external ornament of Psammosteus Taylori 
have turned up. Especially beautiful is one fragment 
recently obtained by Mr Taylor from Newton Quarry, and 
