——, glacial action in, [373].

——, crustaceans of, [376].

——, algæ of, [376].

——, number of plants of, [389].

——, flora of, [399].

Nicotiana, crossed varieties of, [271].

——, certain species very sterile, [257].

Noble, Mr., on fertility of Rhododendron, [252].

Nodules, phosphatic, in azoic rocks, [308].

O.