Birds of Celebes: Cuculidae. 
183 
Distribution. Celebes; — North Celebes (Meyer 1, Faber in Dresd. Miis., Fischer a 1), 
Fur ukaii (Platen); near Tondano (Nat. Coll. inDresd.Mus.), Mount Klabat (Platen 4), 
Kema (P. & F. S.); Matanna-Tomori, Central Celebes (id.); Loka, S. Celebes (id.). 
This Cuckoo is the most aberrant member of the genus Hierococcyx, differ- 
ing, as Capt. Shelley 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 Cuctilus. The bill is ex- 
ceptionally stout and large ; the middle tail-feathers display one or two isolated 
W'hite spots against the shaft, a peculiarity well developed in Ciiculus^ but not 
seen in Hierococcyx except in the present case. The Aving of H. crassirostris is 
also less pointed that in H. sparverioides, the ends of the secondaries reaching 
'Vy of the wing-length as against in the latter species, and about in Ciiai- 
his. 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 Avas first discovered by Meyer in 1871 and Avas only known 
from North Celebes; it would appear to be partial to the hills. Thus, Dr. Platen 
met with it at Furukan (3000 ft.) and on the slopes of Mt. Klabat, and Ave 
have recently receNed a specimen from near the high-lAung lake of Tondano, 
w hil e the Sara sins’ specimen from near Loka Avas 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 lAuir in an adult before us are Avhite barred Avith black; the 
Avhite on the next pair, especially on the outer Aveb, is discoloured Avith rufous 
brown, giving the appearance that the black had become Avashy and had “nin”, 
soaking into the white, with the result of a rufous brown colour. On the third 
pair this process is more advanced, especially again on the more exposed outer- 
web, which is now rufous brown, Avith little isolated pools of Avhite close up to 
the shaft, shoAving where the wLite bars should be, and Avith 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 broAvn of the rest of the Aveb; on the inner Avebs, however, the black 
and Avhite 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 Avebs the black and 
Avhite colours are w^ell separated. On the fifth or middle pair (Cuckoos haA'e only 
ten tail-feathers) where both AA’ebs are exposed, the black and Avhite colours 
are converted on both Avebs into an almost nniform rufous broAvu, except at the 
tip of the tail Avhich is wdiite, the broad terminal band of black, a minute pool 
of AA^ite higher up, and some signs of a black s])ot (the larger half of AA^hich 
is on the inner Aveb), Avhile the shaft partakes of the colours through AAFich it 
passes; nevertheless, on raising the upper tail-coverts and looking at the base 
