Birds of Celebes: Cuculidae. 
183 
Distribution. Celebes: — North Celebes (Meyer i, Faber in Drescl. Miis., Fischer a 1), 
Furukan(Platen); nearTondano (Nat. Coll. inDrescl.Mus.), Mount Klabat (Platen 4), 
Kema (P. & F. 8.); Matanna-Tomori , Central Celebes (id.); Loka, 8. Celebes (id.). 
This Cuckoo is the most aberrant member of the genus Hierococcyx^ differ- 
ing, as Capt. 8helley points out in his key to the species, from the other 
forms in having the under surface of the quills not distinctly barred, except 
at the base, a point which also distinguishes it from Cuculus. The bill is ex- 
ceptionally stout and large ; the middle tail-feathers display one or two isolated 
white spots against the shaft, a peculiarity well developed in Cuculus, but not 
seen in Hierococcyx except in the present case. The wing of H. crassirostris is 
also less pointed that in H. sparverioides, the ends of the secondaries reaching 
Vt of the wing-length as against 7s in latter species, and about 72 in Cucu- 
lus. This form cannot be regarded as a local differentiation of one of the 
wider-spread members of the genus, it appears to be an independent develop- 
ment of a stock now not existing anywhere else. 
The bird was first discovered by Meyer in 1871 and was only known 
from North Celebes; it would appear to be partial to the hills. Thus, Dr. Platen 
met with it at Rurukan (3000 ft.) and on the slopes of Mt. Klabat, and we 
have recently received a specimen from near the high-lying lake of Tondano, 
while the 8 ar a sins’ specimen from near Loka was killed at about 4500 ft. alt. 
The tail-feathers of this species are more than usually instructive in their 
bearing upon the question of changes of coloration provoked by exposure to light. 
The outermost pair in an adult before us are white barred with black; the 
white on the next pair, especially on the outer web, is discoloured with rufous 
brown, giving the appearance that the black had become washy and had “run”, 
soaking into the white, with the result of a rufous browm colour. On the third 
pair this process is more advanced, especially again on the more exposed outer 
web, which is now rufous brown, with little isolated pools of white close up to 
the shaft, showing where the white bars should be, and with the black bars no 
longer reaching to the external edge of the feather, but blackest near the shaft 
and then gradually seeming to melt or become diluted until they pass into the 
rufous brown of the rest of the web; on the inner webs, however, the black 
and white bands are well separated, particularly towards the base of the feathers. 
On the fourth pair the same thing is seen still more advanced, the black bars 
on the outer webs being further reduced, but on the inner w^ebs the black and 
white colours are well separated. On the fifth or middle pair (Cuckoos have only 
ten tail-feathers) where both webs are exposed, the black and white colours 
are converted on both webs into an almost uniform rufous brown, except at the 
tip of the tail which is white, the broad terminal band of black, a minute pool 
of white higher up, and some signs of a black spot (the larger half of which 
is on the inner web), while the shaft partakes of the colours through which it 
passes; nevertheless, on raising the upper tail-coverts and looking at the base 
