178 PICARI®, PICARIAN BIRDS. 
is not shown, however, in the Picidw and some others. The tail is indefinitely 
varied in shape, but the number of its feathers is a good clue to the order. There 
are not ordinarily more than ten perfect rectrices, and occasionally there are only 
eight; the woodpeckers haye twelve, but one pair is abortive; there are twelve, 
however, in the kingfishers, and some others. 
With this slight sketch of some leading features of the group (it will enable the 
«tudent to recognize any Picarian bird of this country at least), I pass to the 
consideration of its subdivision, with the remark, that a precedent may be found for 
any conceivable grouping of the families that is not simply preposterous, and for 
some arrangements that are nearly so. As well as I can judge from the material 
at my command, and relying upon excellent authority for data that I lack, the 
Picarie fall naturally into THREE divisions. These I shall call suborders, not how- 
ever insisting in the least upon the question of taxonomic rank, but simply employ- 
ing the terms conformably with my usage in other cases. The three groups may 
be here tabulated, with remarks calculated to give an idea of their composition : — 
I. CYPSELI— including only the three families Cypselidee, Caprimulgide, and 
Trochilide—the swifts, goatsuckers, and hummingbirds. They are birds of re- 
markable volitorial powers; the wing is pointed, and very long, in its feathers and 
terminal portions, though the upper arm is very short. The feet are extremely 
small and weak, and are scarcely if at all serviceable for progression. The hind 
toe is sometimes versatile (among the swifts) or somewhat elevated (in the goat- 
suckers and some swifts) ; the front toes are frequently connected at base by mov- 
able webbing (goatsuckers), and sometimes lack the normal number of phalanges 
(among swifts and goatsuckers). The variously shaped tail has ten rectrices. One 
family (hummingbirds) shows the tenuirostral type of bill; the other two, the 
fissirostral, on which account they used to be classed with the swallows. The 
sternum is broad, with a deep keel, entire or doubly notched (rarely singly notched) 
behind ; the syrinx has not more than one pair of intrinsic muscles. 
If. CUCULI— comprehending the great bulk of the order; in all, about fifteen 
families, rather more than less. They are only readily limited by exclusion of the 
characters of the preceding and following groups. The sternum is usually notched 
behind ; the syringeal muscles are two pairs atmost. The feet are generally short ; 
the disposition of the toes varies remarkably. In the Coliide, or colies, of Africa, 
all the toes are turned forward. In the Trogonide, the second toe is turned back- 
ward, so that the birds are zygodactyle, but in a different way from all others. 
Families with the feet permanently zygodactyle in the ordinary way by reversion 
of the fourth, or partially so, the outer toe being versatile, are—the Cuculide, or 
cuckoos, with their near relatives the Indicatoride, or guide-birds of Africa; the 
Rhamphastide, or toucans, confined to tropical America and distinguished by their 
enormous vaulted bill; the Musophagide, plantain-eaters or touracos, of Africa; 
the Bucconidcee and Capitonide, or barbets of the New and Old World respectively ; 
and the Galbulide, or jacamars, of America. In the remaining groups, the toes 
have the ordinary position, but sometimes offer unusual characters in other respects. 
Thus in the Alcedinide (kingfishers), and Momotide (motmots or sawbills), the 
middle and outer toes are perfectly coherent for a great distance, constituting the 
syndactyle or anisodactyle foot. The Bucerotide, or hornbills, of the Old World, 
characterized by an immense corneous process on the bill, are near relatives of the 
kingfishers ; so are the Todidw, a group of small brightly colored birds of Mexico 
and the West Indies. Other forms, all Old World, are the Meropide or bee-eaters, 
