possesses so many characteristics distinct from the parent, that for a long time he was considered a separate species, and even assigned a place in a different genus. Enormous nests are sometimes built. John M. Batchelder, Esq., describes one, which he saw in the Saco River, Maine, that was about fifteen feet long, and from one to three feet in height, its position and triangular shape in vertical section being well adapted for securing a change of water, and a hiding-place for the young. The operation of building was very methodical, a hundred and more Eels being at work upon the structure. Water-worn stones, chips of granites and fragments of bricks, sometimes weighing as much as two pounds and transported by a single individual, were utilized in the building. [Illustration: BLACK-NOSED DACE. Constructing Their Nest of Pebbles.] More remarkable, however, than any previously described, are the nests of the Fresh-water Chub, _Semotilus bullaris_, which is known in some localities as the Stone Toter. This fish attains a length of about fifteen inches. The finest nests are on the shores of Westminster Island, but they are common on nearly every island that has a sandy, gravelly shore among the many that make up the Thousand Islands. The nest is a pile of stones, sometimes measuring ten feet across at the base, four feet in height, and containing a good-sized cart-load of stones, weighing in all perhaps a ton. Stones from small pebbles to some four inches in length were used, and as some of the nests are placed at considerable distances from the gravel-beds, and each stone represented a journey, the amount of labor performed, when it is considered that tens of thousands of stones must have been used in the building, certainly was incredible. Each stone is brought in the mouth of the Chub and dropped over the piles, one or more fishes working at the same heap. Some plan is evidently followed in the work, the first deposit of stones being small, and dropped so as to form a circle or semi-circle. The largest heaps are undoubtedly the work of successive years, the nests being annually added to during the last of May or June, when the Chubs are seen lying in the heaps, at which time the eggs are probably deposited. All the labor of piling up is to protect them from predatory fishes, a necessary and wise provision, as cat-fish, rock-bass, perch and others prey upon the eggs. In gravelly beds the Trout excavates a simple nest, a mere depression in the sand, that is not at all incomparable to the nest of some species of gulls. A furrow in the gravelly bottom of a river, often ten feet in length, the depression being made as fast as it is required, is the nest of the Salmon. In Canadian rivers these nests can be easily distinguished by the lighter marking in the bottom.