LOWER LIAS : SEATOW.N. 69 
the Coast-gaard station at Seatown, where about 70 feet of the 
beds, including the upper portion, may be seen. These beds do 
not appear east of Seatown, being let down on that side of the 
valley, below the sea-level, by a fault (noticed by Mr. Day), 
which has a downthrow of from 1 90 to 200 feet. Under the coast- 
guard station the beds are much disturbed and even contorted, 
features partly due to the fault and partly to landslips. 
Oppel grouped part of this series as the " Davoi-bett? charac- 
terized by Ammonites Davcei, A. capricornus, A. Jimbriatus, and 
A. Henleyi. Dr. Wright, who has also spoken of the beds as the 
zone of A. Davcei, included them in the zone of A. Henleyi, but 
unfortunately extended the zone above the Three Tiers, as high 
as the Starfish-bed, whereby he included a series of marls that 
are characterized by A. margaritatus* 
Ammonites latacosta is unquestionably the most characteristic 
fossil, and this species curiously enough has been regarded by Dr. 
Wright as the middle-age condition of A. Henleyi ; while Oppel 
speaks of it as a Capricorn- Ammonite,t and mentions his finding 
25 specimens of A. capricornus at Charmouth. Some specimens 
of A. latcecosta which I have collected, are regarded by Mr. E. T. 
Newton as very near to A. capricornus, and that species has been 
recorded from the Dorsetshire coast by Mr. Etheridge, as well as 
by Oppel as mentioned above. 
There is therefore good reason to classify the beds with the 
zones of A. Henleyi and A. capricornus, although the " Henleyi 
Ammonites " appear in the upper part of the preceding division. 
Among the species which I have collected are A. Bechei, A. 
Henleyi, A. striatus, A. Davcei, and A. Loscombei, forms which 
are also characteristic of the same horizon at Chipping Norton in 
Oxfordshire. A. Loscombei appears to be most abundant in the 
upper part of the Green Ammonite Bedf,J but specimens occur 
in the same block with A, latcecosta. 
The details of the Green Ammonite Beds are as follows : 
Three Tiers (base of Middle Lias). FT. IN. 
f Sandy and ferruginous clay - - -1 
Bluish-grey micaceous marly clay with ironstone > 12 
nodules and iron-stained limestone-nodules -J 
Micaceous flaggy bed, sandy calcareous and 
Zones of 
Ammonites 
ferruginous ; seen on the east side of Golden 
Cap 10 
capricornus and^ Bluish-grey micaceous marly clay - 20 
A. Henleyi. \ Ferruginous band. Ammonites Loscombei ~ \ 18 
about 105 feet. Bluish-grey micaceous marly clay - / 
Occasional bands of indurated marl or limestone"] 
Bluish-grey marly clays with nodules of hard I 54 Q 
grey limestone and ferruginous bands. [ 
[_ Ammonites latacosta, A. striatus, Inoceramus. J 
The above thicknesses are estimates taken from measurements at different 
places, where the thickness varies a good deal : indeed on the eastern side of 
Golden Cap a thickness of 125 feet was measured, from the base of the loweat 
lier to the top of tbe Belemnite Stone. 
* Wright, Lias Ammonites, pp. 89, 420. 
f Juraformation, pp. 155, 157. 
See also Day, Quart. Journ. Geol. Soc., vol. six. p. 291. 
