THE LIVING WORLD. 
305 
tomary usages of birds, leaving the nest at infrequent intervals to keep up old 
acquaintances, through occasional visits, she becomes an astonishing example of 
exclusiveness, for she goes in upon the nest and then seals up the exit, care¬ 
fully plastering up the hole with her own ordure, and leaving only a small 
slit through which to receive the food brought to her by the male. She is 
therefore unable to leave the nest until the young is hatched, her liberation 
being then accomplished by the joint efforts of herself and mate. Should the 
plaster which confines her be broken before the hatching is completed, she 
seems to be almost help¬ 
less, and if put upon the 
ground is so stiff and 
nearly featherless that she 
is unable to rise even to 
the lowest branches. 
The larger species of 
hornbills have powerfully 
developed wings, but their 
bodies are so heavy that 
flight is awkward and seem¬ 
ingly very laborious. When 
several take wing together 
they produce a noise not 
unlike a locomotive when 
getting under way with a 
heavy load. 
THE CUCULID.SE, OR CUCKOOS. 
The order of birds 
under which cuckoos are 
classed is a very large one, 
numbering a hundred spe¬ 
cies, and found in nearly 
all countries. The popu¬ 
lar name proceeds from the 
familiar note it utters most 
frequently at early dawn. 
The great variety of species 
presents a remarkable dis¬ 
similarity of appearance, 
ranging between that of 
a timid sparrow to a strik¬ 
ing resemblance which at 
least one species (cuculus canorus) presents to a small hawk, while several show 
all the markings of falcons, and also of the shrike. Only in one respect do 
the several varieties exhibit a common characteristic, unless we are critical 
enough to look below the exterior. They are all parasites (save the few 
American species) in respect to laying the ireggs in the nests of other birds and 
imposing the care of their young to these enforced foster-parents.. Concerning 
this singular habit Mr. Seebohm, an excellent authority, thus writes: 
20 
RED BILLED TOUCAN. 
