few minute glittering points of light, representing the loftier portions of the chain, remain to indicate its position.  Madler expatiates on the sublime view which would be obtained by any one standing on the highest peak and observing the setting sun on one side of him and the nearly “full” earth on the other; while beneath him would lie a vast plain, shrouded in darkness, surrounded by the brilliantly illuminated peaks on the lofty border, gradually passing out of sunlight.  In addition to the central mountain range, there are some large rings, craters, hillocks, &c., on the floor; and on the inner slope of the W. border there is a very large circular enclosure resembling a ring-plain, not recorded in the maps.  Schmidt shows a row of large craters on the outer slope of the E. border.  Of these, one is very conspicuous under a low evening sun, by reason of its brilliant walls and interior.  In the region between Gauss and Berosus is a number of narrow steep ridges which follow the curvature of the E. wall.

STRUVE.—­A small irregularly-shaped formation, open towards the S., forming one of the curious group of unsymmetrical enclosures associated with Messala.  Its dark floor and a small dusky area on the N. indicate its position under a high sun.

CARRINGTON.—­A small ring-plain, belonging to the Messala group, adjoining Schumacher on the N.W.

MERCURIUS.—­This formation is 25 miles in diameter.  A small crater stands on the S.E. section of the wall.  There is a longitudinal range in the interior, and on the W. and N.W. the remains of two large walled-plains, the more westerly of which is a noteworthy object under suitable conditions.  A short distance S. is a large, irregular, and very dark marking.  On the N., lies an immense bright plain, extending nearly to the border of Endymion.

WEST LONGITUDE 60 deg.  TO 40 deg.

TARUNTIUS.—­Notwithstanding its comparatively low walls, this ring-plain, 44 miles in diameter, is a very conspicuous object under a rising sun.  Like Vitello and a few other formations, it has an inner ring on the floor, concentric with the outer rampart, which I have often seen nearly complete under evening illumination.  There is a small bright crater on the S.E. wall, and a larger one on the crest of the N.E. wall, with a much more minute depression on the W. of it, the intervening space exhibiting signs of disturbance.  The upper portion of the wall is very steep, contrasting in this respect with the very gentle inclination of the glacis, which on the S. extends to a distance of at least 30 miles before it sinks to the level of the surrounding country, the gradient probably being as slight as 1 in 45.  Two low dusky rings and a long narrow valley with brilliant flanks are prominent objects on the plain E. of Taruntius under a low evening sun.

SECCHI.—­A partially enclosed little ring-plain S. of Taruntius, with a prominent central mountain and bright walls.  There is a short cleft running in a N.E. direction from a point near the E. wall.  Schmidt represents it as a row of inosculating craters.