THE NESTING HABITS OF THE BAY A. 633 



side to side to act as a perch on which he sits. In the • jhoohi ' I have 

 often found dabs of mud against the side on irhick 1 have found fire-jlies. 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 mate, as 

 generally the insects are so embedded in the mud as to be incapable of moving 

 or emitting any phosphorescent light. Another thing, I have found small grubs 

 and caterpillars in the mud of the • jhoola,' which emit no phosphoric light, 

 and which could only be imprisoned by the baya bud for food. The baya, 

 as you know, is a grain-eater, but, like all grain-eating birds, feeds the young 

 when just hatched on soft grubs and insects.' " The second witness brought 

 forward by Major McNair is Captain Barry de Hamel of the Straits Settlement 

 Police, who writes : " I 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 

 fire-flies 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. My 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." Major McNair's third witness is 

 another correspondent from Singapore, who writes : "One of Simon Coorozos ' 

 boys says that when at Tanjaig Katong a short time ago, he and some other 

 boys found a weaver-bird's nest with three young ones, and also saw sticking 

 in the mud three fire-flies." 



Let us now consider for a little this evidence. That of Captain Ban-y 

 de Hamel and of the correspondent from Singapore is, I submit, not worthy 

 of acceptance inasmuch as it is hearsay only, and the hearsay of uneducated 

 native witnesses who are notoriously untrustworthy. Men of science 

 admit evidence far too freely and this accounts for some of the absurd 

 theories which are generally accepted. Very little attempt appears to be n.ade 

 by the average zoologist to sift the various kinds of evidence submitted to him. 



If a statement agrees with any theory he enunciates, he accepts it without 

 scrutiny, but if it is opposed to his theory he ignores it, or accepts it and tries 

 to explain it away ! This, of course, is not the proper spiiit in which to accept 

 evidence. All evidence should be carefully sifted and scrutinised ; in fact, 

 the same tests should be applied to it as courts of law apply. 



If we apply such tests to the evidence of the fire-fly theory, we are forced to 

 reject the testimony of the two last of McNair's witnesses. 



The evidence of Mr. Buckley is fii'st-hand and should therefore be 

 received. He states that he has found fire-flies on the mud in bayas' nests ; 

 but that these are generally so deeply embedded as to be incapable of moving 

 or emitting any phosphorescent light. He further states that he has also found 

 embedded in the mud non-phosphorescent insects. 



Before this evidence can be said to afford any support of value to the fire- 



