70 
Allen’s naturalist’s library. 
the chamber was reached. In this, particular instance the 
tunnel and nest-chamber were quite clean, but these are some- 
times in an c.xtremely dirty condition, and Mr. .Seebohm men- 
tions that in one which he examined, “the bottom of the 
passage was lined with a black or dark green glossy substance 
smelling strongly of fish, and almost as sticky as bird-lime." 
This is formed of the castings and droppings of the birds, and 
the mass often swarms with maggots. The eggs are generally 
laid upon a small heap of white feh-bones, cast up by the birds, 
and this constitutes the whole of the “nest.” 
Eggs. — Six or seven, rarely eight or nine, in number. They 
are pure white, very glossy, and nearly round. Axis, 0^95 inch ; 
diam., 075 inch. 
THE ROLLERS. SUB-ORDER CORACI.®. 
These birds constitute a group of Old-World Picarians, of 
brilliant colour and somewhat Crow-like in form. They are 
undoubtedly nearly allied to the Kingfishers and Bee-Eaters, 
though they have not got the long bills of the two last-named 
groups of birds. The palate is desmognathous, or “ bridged,” 
and there are rudimentary basipterygoid processes, while the 
breast-bone has four notches in its posterior margin. The 
feet in the Rollers are very much like those of the Kingfishers, 
that is to say, “ Anisodactyle,” the soles being fiat and the toes 
united together for a short distance by a membrane, the outer 
one being joined to the middle one at the extreme base, and 
to the inner one for the basal joint. The Family of Rollers is 
divided into two Sub-families, the Ground Rollers {Brachy- 
pteraciime) and the True Rollers (Coraciina). The former 
contains three ground-loving genera, all remarkable for their 
very long legs, and confined to Madagascar, while the True 
Rollers are found in the temperate and tropical portions of the 
entire Old World. 
THE TRUE ROLLERS. FAMILY CORACIID^. 
The species of Coraciidee at present known to us are but 
twenty-one in number, and they are contained in two genera. 
