THE GEOLOGIST. 
iug strata overlying the pipes botli in the chalk and magnesian lime- 
stone, for it assists in corroborating the views of Mr. Prcstwich. 
For a full exposition of the theory I have adopted, I would refer 
to Mr. Prestwich's most able paper " On the Origin of the Sand- 
and Gravel-pipes in the Chalk of the London Tertiary District," 
" Quart. Jour. Geol. Soc," vol xi., p. 64. 
ON THE OLD RED SANDSTONE AND ITS FOSSIL FISH 
IN FORFARSHIRE. 
By W. PowRiE, Esq. 
As anything calculated to thi'ow light on the peculiar fauna of the 
Old Red Sandstone period must be interesting to geologists, I send 
you a short notice of some fossils lately found in the flagstones of 
Forfarshire, which may aid in adding to our knowledge of the pecu- 
liarities of the creatures found in these rocks. 
Some six weeks ago, by far the finest specimen of Pterygotus 
anglicus yet found Avas discovered in the " pavement" quan-ies of 
Cannyllin : this superb specimen is now in the Arbroath Museum. 
This fossil, coming clean out from the matrix in which it was 
imbedded, consists of all the body-segments, a part of the caudal 
plate being also preserved and well seen in the cast from which the 
fossil had been lifted. It shows no features absolutely new or 
hitherto unknown, but it is nevertheless very interesting, as exhibit- 
ing the manner in which both the dorsal and ventral portions of this 
creature had been covered and protected by strong sculptured plates. 
It also proves that Mr. D. Page was quite correct in the place which 
he latterly assigned to the curious duck-bill like plate with its 
vnng-like appendages, which, as noticed in Hugh Miller's " Old Red 
Sandstone," occasioned the name of " Seraphim" to be applied to 
this fossil. It is found in situ, covering the under portions of the 
segment next the head. In all probability, as suggested by Mr. 
Page, it formed part of the sexual organs of this ci-eature, and also a 
covering for the vent or anal opening, there being no vestige of any 
such opening in cither the sub-caudal segment, in the portion of the 
caudal plate, or telson, presei'ved, or on the junction of these seg- 
ments. It gives some idea of the manner in which the different 
plates forming the body-segment joined into one another, the joinings 
being seemingly of such a nature as to allow the creature consider- 
able powers of curvature. It also shows its comparative length and 
breadth, although in this respect it seems to differ from other speci- 
mens, showing a rather greater proportional length ; but this might 
have been occasioned by those belonging to different sexes, the one 
being probably of a more slender form than the other. The head 
•with all its appendages is wanting. The entire length of the fossil, 
