130 BULLETIN 2 08, UNITED STATES NATIONAL MUSEUM 



far forward past her neck as if he gripped the side of her upper neck; . , . after 

 several seconds of treading, loud scream-chattering broke out in urgent manner 

 and continued during the latter part of the act. It was not possible to detect 

 which bird uttered this. Still uttering the sound they broke apart, and, one 

 closely behind the other, they shot along in extremely rapid chasing-fleeing flight 

 under the trees into the forest growth and out of sight; the screaming-chattering 

 (rather in the nature of a distress utterance) came to an end. Then there occurred 

 a drumming flight above the treetops of the forest patch; two circhng movements 

 in rustling flight were made, and this was concluded by the birds' shooting over 

 the trees of the upper forest margin above me still "rustling," diving, in among 

 the trees where copulation had occurred, and then disappearing in silence. 



The Rustling Flight 



The drumming or rustling flight is a matter of considerable interest 

 as it or something very similar occurs not only in Indicator indicator 

 but also in /. minor and Alelichneutes robustus, the lyre-tailed honey- 

 guide of the West African equatorial forests. Ranger's fortunate ob- 

 servation is the only one we have to date in which this performance 

 appears to be definitely connected with the mating activities of the 

 bird, although in the few other cases of its observation it was also 

 given by birds at or near their favored call trees. I know of at least 

 three such instances in South Africa and Southern Rhodesia. Van 

 Someren's observation, cited on page 124, seems to have been a fourth 

 instance. A similar case in Nigeria noted by Hutson (Hutson and 

 Bannerman, 1931, p. 200) may also have been at or near a call tree, 

 although he was not aware of the call-tree phenonemon. 



Hutson writes that "once a bird was seen flying round and round 

 a clump of tall trees making a distinct whirr with its wings, after 

 which it perched on top of a tree to utter a series of 'sweet beers.' " 

 "Sweet beer" is apparently the same as the notes I refer to as vic-tor 

 or whit-purr; the tall trees may well have been call posts, and the 

 fact that immediately after finishing the rustling flight the bird called 

 a series of these notes further suggests the same thing. I have never 

 experienced this note except at a call post, but I have data from other 

 observers that indicate it is sometimes given elsewhere — possibly from 

 "temporary" call posts or from trees which may have been call posts 

 but were not known to be such by the observers. 



Recently, Neuby-Varty made another interesting observation re- 

 garding the rustling flight. An adult male greater honey-guide was 

 being watched giving its vic-tor call from a favorite tree when a 

 second honey-guide arrived. Both birds then moved to the center 

 of the tree where the foliage unfortunately hid them from view. After 

 about half a minute one of them flew out at great speed and seemed 

 almost as if it had gone mad, flying forth and back, through and around 

 the tree, all the time making a noise in bursts of two to three seconds 



