Birds of Celebes: Caprimulgidae. 
325 
Steatornithidae.^ according to Mr. Beddard, are not far removed — it is never- 
theless well to be made aware of the differences which separate the several 
groups. Some of these differences may be recapitulated as follows: 
Cap rimulginae 
Nyctihiinae 
Podarginae 
Aegothelinae 
SteatornitJiinae 
Phal. in outer toe 
Four 
Five 
Five 
Five 
Five 
Claw of middle toe 
Pectinated 
Not pectinat. 
Not pectinated 
Not pectinated 
Not pectinat. 
Oil-gland . . . 
Pres, (small) 
Present? 
Absent 
Absent 
Present 
Powd.-dwn. patches 
Absent 
Present 
— 
— 
— 
Syrinx .... 
Tracheo- 
bronchial 
— 
Approximates 
hr onch . structure 
Tracbeo-bron- 
chial 
Bronchial 
Stern., nr. of incis. 
One pair 
Two pairs 
Two pairs 
Two pairs? 
One shallow 
pair 
Palate .... 
Aegitho- 
gnathous i) 
Schizognath. 
D esmognathous 
Desmognatb.? 
Desmognatb. 
Biceps-shp . . . 
Present 
— 
Absent 
Absent 
Absent 
Fem.-cand. muscle 
Present 
— 
Present 
Present 
Absent 
Caeca 
Present 
— 
Present 
Absent 
Present 
Food 
Insectivorous 
Insectivorous 
Insectivorous 
Insectivorous 
Frugivorous 
Eggs 
Coloured 
— 
Pure white 
Do., or palely 
striated 
Pure white 
Nest 
None, eggs 
laid on 
ground 
Flat, of small 
sticks on horiz. 
branches 
In hollow trees 
In caves 
In external appearence the Podarginae are very like the Ngctibiinae\ struc- 
turally they differ in at least one very important point, i. e. the structure of 
the palate. Nevertheless in this respect also the two subfamilies approach one 
another more nearly than the other Caprimulgidae'. “we have almost a transition 
to the Desmognathous structure in Ngctihius’^ (Huxley, P. Z. S. 1867, 456). 
It is remarkable that Australia, the part of the world almost the most 
remote from South America, should furnish the link, Podargus^ between the 
South American forms Ngctibius and Steatornis, which would otherwise be best 
separated as families for themselves. The distribution of the Capy'imulgidae may 
be compared with that of the Struthiones. But it seems to have taken place 
at two distinct epochs; — an earlier one when the dispersal of the main groups 
took place, and a later one which determined that of the subfamily, Caprimul- 
ginae. The latter group from its great richness in genera, may be supposed to 
have been longer in America than elsewhere, the various structural modifications 
being a matter of time. The Palaearctic Begion possesses only the cosmopolitan 
genus Caprimulgus., which most likely entered it from America in comparatively 
recent times ; while Lgncornis and Eurostopodus and the peculiar Caprimulginae of 
Africa seem to have proceeded south and become isolated after an exodus from 
America at an earlier period. 
1) cf. Hartert, Ibis 1896, 370. 
