UOUN EXPIvDITION NARRATIVE. 135 



Wt' liciird the noise attributed tu tlie spider, but came to tlie conclusion that 

 it was made by a bii'd— probably a quail. It is a noteworthy fact that the noise 

 is principally heard at the time when birds, such as quails, are most a1)undant. I 

 could lind no sti'ucture which could enable it to make any such noise as is 

 attributed to it, but at the same time our observations of the animal in captivity 

 led to the discovery that it does possess a well developed stridulating organ. 

 When irritated it rises on its hind legs, and rubbing its palps against its maxilla; 

 produces a low whistling sound. The structure of this organ is described and 

 figured in the Zoological section of the Report. There is a series of little still" rods 

 on the maxilla which rub across a series of curious little flattened " keys " on the 

 pal]) and so i)roduce the low whistle. The animal is closely allied to a spider from 

 Assam, in which Professor Wood Mason many years ago descriljed a very similar 

 organ, and since then, in fact since we found the organ in Phlogius crassif>es, it has 

 been shown Ijy Messrs. Pocock and F. 0. P. Cambridge that stridulating organs of 

 various kinds are more connnon than was previously thought. 



All the specimens captured while I was staying at Alice Springs and since 

 then have, unfortunately, been females, so that we do not know if the organ exists 

 in the male, but from the fact of its occurrence in the former it is perhaps to l>e 

 regarded as an organ for producing a warning signal to warn ofl' would-be 

 aggressors. At the same time it must be said that this is merely a theory which 

 has not Ijeen put to the test, as we do not know either who its particular enemies 

 are or whether they are capable of hearing the sound made. If they be, as 

 proljaljly they are, ground animals such as the smaller marsupials or lizards it 

 may, especially in the case of soft-bodied animals through whose skin its powerful 

 jaws can bite, act as a deterrent. In its burrow we found remnants of beetles 

 upon which it had evidently l)cen feeding. During the night, as it is nocturnal, it 

 is doubtless active, but during the day time when taken out of its burrow it is 

 very sluggish, and can easily Ije handled. 



What with the days .spent either in examining and sketching the animals 

 brought in by the blacks, or in collecting out amongst the hills and the e\cnings 

 in developing photographs taken during the ilay and in long talks and discussions 

 on anthropological sulijects with Mr. Gillen, some of whose vaJua-ble notes relating 

 to the customs of the Aruuta tribe are published \n the Report of the Expedition, 

 my time at Alice Springs soon passed away. Mr. Watt had returned fr(jni his 

 flying visit to the gold and "ruby" fields, and at midnight on 5tli ^Vugust, with 

 the temperature below freezing point, we left the station on our southw.ird jdurni^y 

 along by the overland telegraph line. 



