addition to those already referred to, a number of mysterious dark spots
were discovered by Schmidt in the dusky region about midway between
Copernicus and Gambart, which Klein describes as perforated like a sieve
with minute craters. A short distance south-west of Copernicus stands a
bright crater-cone surrounded by a grey nimbus, which may be classed with
these objects. It is well seen under a high light, as indeed is the case
with most of these features.

CRATERLETS, CRATER-PITS.--To a great extent the former term is needless
and misleading, as the so-called craters merge by imperceptible
gradations into very minute objects, as small as half a mile in diameter,
and most probably, if we could more accurately estimate their size, still
less. The crater-pit, however, has well-marked peculiarities which
distinguish it from all other types, such as the absence of a
distinguishable rim and extreme shallowness. They appear to be most
numerous on the high-level plains and plateaus in the south-western
quadrant, and may be counted by hundreds under good atmospheric
conditions on the outer slopes of Walter, Clavius, and other large
enclosures. In these positions they are often so closely aggregated that,
as Nasmyth remarks, they remind one of an accumulation of froth. Even in
an 8 1/2 inch reflector I have frequently seen the outer slope of the
large ring-plain on the north-western side of Vendelinus, so perforated
with these objects that it resembled pumice or vesicular lava, many of
the little holes being evidently not circular, but square shaped and very
irregular. The interior of Stadius and the region outside abounds in
these minute features, but the well-known crater-row between this
formation and Copernicus seems rather to consist of a number of
inosculating crater-cones, as they stand very evidently on a raised bank
of some altitude.