..The fishes of Illinois . nd Montana. Its habits are those of its subfamily. It often lies with its head upand its body bent to one side or supported partly by a stone. It canturn its head without moving its body; can roll the eye about in thesocket; may rest suspended, as we have seen it do, on the under sideof a floating board ; and sometimes buries itself, with a whirl, in thesoft sand, so that only its eyes are visible. The food of a dozen specimens was so uniform that they mayfairly be taken as representative Two thirds of it consisted solelyof Chironomus larvae, 7 per cent, of other min
..The fishes of Illinois . nd Montana. Its habits are those of its subfamily. It often lies with its head upand its body bent to one side or supported partly by a stone. It canturn its head without moving its body; can roll the eye about in thesocket; may rest suspended, as we have seen it do, on the under sideof a floating board ; and sometimes buries itself, with a whirl, in thesoft sand, so that only its eyes are visible. The food of a dozen specimens was so uniform that they mayfairly be taken as representative Two thirds of it consisted solelyof Chironomus larvae, 7 per cent, of other minute larvae of gnats, andthe remaining 12 per cent, of larvae of small May-flies. The species spawns in spring, from the last of April to the first ofJune. Females were depositing their eggs in our aquarium at Mere-dosia, April 28 and 29, 1899. In the act of spawning the male rodeon the back of the female, with ventrals astride, and pectorals andventrals in active vibration as the pair moved about on the bottom. 0$$ Wjifl i. ^ < O BOLEOSOMA TESSELLATED DARTERS 297 The eggs are emitted at intervals, and from time to time the femaleraises a cloud of sand by a vigorous beating with the tail, perhaps forthe purpose of covering them. Males in breeding dress have thefirst dorsal spines more or less swollen, and club-shaped at the tip. In studying our collections, wide variation was noticed with re-spect to the scaly covering of the breast and cheeks, ranging fromcomplete nakedness to complete scaliness of both, and also a con-siderable variation in robustness of build. While, generally speaking,specimens become more scaly northward and more slender south-ward, it was not possible to make out, even approximately, any lineor area of division, either general or local, between the two forms, orto draw any definite dividing line among the variants confusion of conditions may be illustrated by the followinganalysis of a single collection of forty-six specimens (Accessions
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Keywords: ., bookcentury1900, bookdecade1900, bookidcu31924, booksubjectfishes
