202 
DARTER, OR SNAKE-BIRD. 
DARTER, OR SNAKE-BIRD.*— PLOTUS ANHINGA. 
Plate LXXIV. Fig. 1. Male. 
Plotus anlilnga, Linn. Syst. ed. 12. tom. i. p. 218. Gmel. Syst. i. p. 580, 1. 
Jnd. Orn. p. 895, 1. — Plotus melauogaster. Id. p. 896, var. B, var. C. — An- 
Linga Brasiliensis Tupinamb. Afarc^mu. Hist. Nat. Bras. p. 218. — L’Anbinga, 
Briss. vi. p. 476. Salerne, p. .375. Buff. Ois. viii. p. 448. — Anbinga noir 
de Cayenne) PL Enl. 960. — Wliite-bellied darter, Lath. Gen. Syn. iii. p. 622, 1. 
— Black-bellied darter. Id. p. 624, var. A, pi. 106. Id. p. 625, var. B Colym- 
bus colubrinus, snake-bird, Bartram, p. 132, 295. — Beale’s Museum^ No. 3188 ; 
male. 
PLOTUS ANHINGA.— 
Plotus anbinga, Bonap. Synop. p. 411. — Plotus melauogaster, Ord. 1st edit, of 
Supp. p. 79. 
Head, neck, whole body, above and below, of a deep shi- 
ning black, with a green gloss, the plumage extremely soft 
* Named in the plate, black-bellied darter. 
This very curious genus contains only two known species ; — that of our 
author, common to both continents of America, and the Plotus Vaillantii of 
Temminck, a native of India, Africa, and the South Seas. It has been placed 
among the Pelicanidce by most ornithologists ; but how far all the forms which 
are at present included in that family have a right to be there, I am not at pre- 
sent prepared to determine : if they are, that of Plotus will hold a very inter- 
mediate rank, particularly in habits, which may lead to some discoveries in the 
relations to each other. The economy is in a considerable measure arboreal, 
and in their own family, as now constituted, they show the greatest develope- 
ment of the power of diving, and activity in the water. They show also the 
extreme structure in the power of darting and suddenly again withdrawing 
their head. The cormorants and herons possess this power to great extent, and 
they all possess a peculiar bend of the neck, observed in certain circumstances of 
the bird’s economy, and into which that part at once puts itself when the bird 
is dead. This is produced chiefly by the action of two muscles; the one 
inserted within the cavity of the breast, and running up with a long tendon 
to the vertebre beneath the bend ; the other inserted in the joint above the bend, 
and running far down with another slender tendon. The action of these two 
powers, resisted by the muscles on the back part, produce the peculiar angular 
