A MONOGRAPH OF PLOCEUS BAY A 
47 
breeding nest of these Bayahs ; besides the nest proper the male 
builds a ‘jhoola’ or swing for himself alongside this breeding 
nest. This ‘jhoola’ is about six inches long and open at the 
bottom, with a bar of worked grass from side to side to act 
as a perch upon which he sits. In the ‘jhoola’ I have often 
found dabs of mud against the side, on which I have found fire- 
flies. The natives say the male bird puts them there to light up 
his ‘jhoola.’ My own opinion is that he rather puts them in as 
a store of food for his male, as generally the insects are so 
embedded in the mud as to be incapable of moving or of emitting 
any phosphorescent light. Another thing, I have found small 
grubs and caterpillars in the mud of the ‘ jhoola,’ which emit no 
pliosphoric light, and which could only be imprisoned by the 
Bayah bird for food. The Bayah, as you know, is a grain eater, 
but, like all grain-eating birds, feeds the young when just 
hatched on soft grubs and insects. These birds inhabit the 
foot-hills of the Himalayas and sub-mountain districts for the 
greater part of the year, and only with the in-setting of the rains 
does it wander over the plains to nest. What is not so com- 
monly known is that the same Bayahs will, year after year, visit 
the same neighbourhood to nest and will choose the same trees, 
and that this habit of the Bayah has brought about a distinct 
change in the colour of the birds. The families which breed in 
the arid portions of the Punjab, Scinde, Rajputana, and Beloo- 
chistan are lighter coloured, the yellow is more gamboge than 
golden yellow, the brown of the nape, back and scapulars is 
duller, and the under-feathers lighter in colour. Major McNair’s 
description is accurate in regard to the Bayah who breeds in the 
more fertile and greener plains. The Bayah uses for nest- 
building the grass known as ‘ surput ’ and ‘ sirkunda.’ 1 am not 
sure, but think botanically it is called Saccharum Sara.” 
I also further prosecuted my inquiries and wrote to Captain 
Barry de Hamel, of the Straits Settlement Police, who, in a reply 
dated May 26, 1900, from Province Wellesley, Penang, says : 
“ 1 have made fairly exhaustive enquiries into the question of 
the mud particles in the nest of the Baya birds. My informants 
all seem decided as to one point, and that is, that .the mud is 
really used to place fireflies upon, and I have met people who 
have actually seen them there. I have seen no one, however, 
who has ever found any other species of fly or insect within the 
nest. ^ly informants are undecided, however, as to two points ; 
the one party argue that the fly is used essentially as a lamp to 
guide the parent birds at nights ; the other, that it is a special 
delicacy for the youthful birds to fatten upon. It may possibly 
serve for both purposes, the fly, when too weak to give further 
light, being eaten. I am trying to get a nest of young ones, and 
getting a few fireflies to place them on the mud and watch the 
result. It is just possible that the mud may in some way 
nourish the firefly, hence I wish to see if the fly is eaten, or 
changed, or remains the same. The ‘ peepit,’ may I point out. 
