116 H. J. JOHNSTON-LAVIS ON THE GEOLOGY 
metre 
Puase VI,, Period 1. Hard brownish grey compact pumice,............ 0°50 
graduating into partly rounded lapilli with more pumice 
at thestop 2... os...0deescumee ance creed ese eee eee 3°50 
Period 2? Yellowish dusty soil, with blocks of much de- 
composed lava (rare), and bits of white 
PUMICE. 220 e cede as whe ace cents ee ee 1:00 
Rounded or subangular, grey, light pumice, 
yellow coated, with very thin ash beds, pass- 
ING WP UNO eco so-kns «os endian 0:80 
Yellow dusty, or loamy soil, with fragments 
of the underlyme pumice -....:.4-.:5.- see 1:00 
Period 3... Whate, light pumice °..;........c.02.2-sesee eee 0°75 
Yellow ashy SOs. 20.202 s.0:0.0..0-.-0se7e see 1-00 
Period 4. White, rather light pumice, rich in sanidine, 
together with a few foreign ejected blocks ... 0°40 
More compact, greenish grey pumice, mixed 
with more foreren blocks, .........0-:.ceseseeeeee 2°60 
Fine grey pisolitic tufa, passing up into......... 0°75 
Puase VII., Periods 1 to 3. The same, non-pisolitic ................00000 1:25 
Period 4. Black, pumiceous scoria, enclosing broken leu- 
cite crystals, with subangular lapilli, and 
GUStis i eceinticis doenteaceiGents sacs coe 0:80 
Fine ash, false-bedded. .ss.2.).. <0 sevceeee esse eee 0°80 
Period 5. Light, black, vitreous scoria, with an inter- 
laminated. band of pink lJapilli ......2. 3. 22ce-ce-eeeeeeee 1:00 
Nortr. A few yards beyond where this section was taken, the valley curves to 
the west, and in the section there presented nearly every member can be seen 
to rest unconformably on the denuded surface of the bed below.—Vide Fig. 2, 
poly 
SECTION 6. Stone-quarry at Cisterna. This section is taken in the quarry belong- 
ing to Signor Francesco Monte. It is the first one encountered after 
leaving Cisterna on the road to Marigliano. There are others along the 
same road, showing similar deposits, and demonstrating the presence of 
a coarse leucilitic lava of unknown thickness, and at least more than 
half a kilometre broad. 
Puase I. Lava, rather porous, and decomposed at 
metres. 
the top, highly 
crystalline, the leucite, pyroxene, and olivine being 
large and well developed. Quarried down to drainage- 
Level: »+,.ccctenmeeree ce Meee REC e EERE 
Puasss IL., III., IV., V., & VI., Period 1. Yellow, decomposed soil, 
with rotten, white (?) pumice............ 
Period 2. Light grey, spongy pumice, yellow dust, &.... 1:00 
Period 2 or SY Wine ash WR Anes. ci ieee. 22. eee 0°10 
Period 4, White sanidinic, and greenish-grey compact 
pumice, with fragments of ejected blocks .................. 0-12 
Puasses VII. & VIII. Modern vegetable soil .:............1...0esceceeseee 0:90 
SECTION 7. Lagno di Trocchia. Sectiontaken on the north side of the valley 
below the space included by the contour-lines of 250 and 260 metres. 
metres. 
PuasE VI., Period 1. Fine grey lapilli, earthy at top..................-.. 0°30 
Hard, brownish grey, compact,pumice ......... 0-80 
Pertod 2. Yellow pumiceous soil .<..........<......2.0ssseeeee 2°50 
Rounded, grey or yellowish spongy pumice, 
with yellow soil (false-bedded).................. 1:50 
Period’ 3. ‘Coarsebreteta Sgeap pes <n. <5 0 22~e -2< eee 6:00 
False-bedded breccia, coarse in patches, with a 
little white pumice......... (eves sevens sone eeeeeen 8:00 
Fine yellow earilty...5...:..--.csra.-0-+.-0- ese 1:00 
