Sclater on the Sy sterna Avium. 75 
With these additions the Anisodactylas, as we have called them 
in our 4 Nomenclator,’ will consist of the following twelve 
families : — 
1. Coliidse. 
2. Alcedinidse. 
3. Bucerotidae. 
4. Upupidae. 
5. Irrisoridae. 
6. Meropidae. 
The Heterodactylae, which follow next in the 4 Nomenclator/ 
consist of the single family Trogonidae, the only form of the 
whole class of birds in which the fourth or outer digit is reversed 
instead of the second. The pterylosis of Trogon is also quite 
different from that of the other Zygodactylae, being purely pas- 
serine, except as regards its long aftershaft.* 
The true Zygodactylae in the ‘Nomenclator’ consist of four 
families besides the Cuckoos, namely the Galbulidae, Bucconidae, 
Rhamphastidae, and Capitonidae. To these must be added the 
Indicatoridae, which do not occur in the New World. Indica- 
tor has now been conclusively shown to have nothing to do with 
either the Cuckoos (as supposed by the older authors) or with 
the Woodpeckers (as believed by Blythf), but must form a 
family of itself, allied to the Capitonidae. J 
Lastly, I would now propose to place together in one group, 
under the restricted title of 44 Coccyges,” the two families Cucu- 
lidae and Musophagidae. I am not yet prepared to remove them 
to the neighborhood of the Gallinae altogether, but (as above 
stated) am ready to allow that Prof. Garrod has shown good 
reasons for separating them from the rest of the Zygodactylae. 
Moreover, on the whole, I have come to the conclusion that, 
looking to the successful assaults that have been made on Prof. 
Huxley’s views as to the nature of the palate in the Pici and in 
the Trochilidae, it will be a better arrangement to sink the Pici 
and Cypseli to the rank of suborders and to revive the term 
Picariae for the whole of the three groups denominated in the 
* Nitzsch, Pterylogr. p. 93. 
t J. A. S. B. xi. p. 167 (1842). 
% Cf. Sclater, Ibis, 1870, p. 176. For the species of Indicator consult Sharpe in Row- 
ley’s Orn. Misc. i. p. 192, and P. Z. S. 1878, p. 793. 
7. Momotidae. 
8. Todidae. 
9. Coraciidae. 
10. Leptosomidae. 
11. Podargidae. 
12. Steatornithidae. 
