86 Jackson, Notes on Tooth-hilled Bower-Bird of N.Q. [J^ 



Emu 

 Oct. 



In dealing with the specimens of the leaves collected I have to 

 acknowledge the kind help accorded to me by Mr. J. H. Maiden, 

 F.L.S., Government Botanist of New South Wales, to whose hel]:» 

 in classification and naming I am deeply indebted. The collection 

 made has more than mere specimen value — it gives some idea 

 of the big task which the industrious apprentice in home decoration 

 undertook every day in the period immediately prior to nesting. 

 Some of the larger and more thickly-stemmed leaves show how 

 tough a job the bird had (in spite of its serrated bill) to sever the 

 leaf. This is especially noticeable in the case of some of the large 

 leaves of the tree Cryptocarya mackinnoniana (No. i in plate), 

 the stems of which are exceptionally thick and tough : the 

 stem of one of my specimens measures 0.20 inch in diameter at the 

 point of severance. From the collection made I have selected 

 a set comprising the 14 species I found used, which will be 

 seen in the two accompanying photographs, one of which shows 

 the natural under sides of the leaves, and the other the 

 upper sides of three and the under sides of six leaves. It will 

 be noticed that the leaves are mostly braced on the under side 

 with strong ribs. There is, however, one exception to this rule 

 of selection by the bird of strongly-ribbed leaves. This occurred 

 in localities where the wild ginger plant {Elettaria scottiana, No. 12) 

 was a feature of the scrub growth. The only rib in these long, 

 narrow leaves was the central one, extending the whole length, 

 and consequently where these leaves were used to carpet the play- 

 grounds they were often found considerably curled. Of course, 

 in the fierce northern heat all leaves, of whatever sort, would 

 eventually curl, but the majority of those chosen would meet the 

 bird's evident craze for tidiness for, at any rate, one day, and 

 I only come to the obvious conclusion that his invariable practice 

 of choosing leaves that would not curl readily, so placing them 

 upside down that the curling tendency was counteracted, and 

 finally rejecting them when they did curl, was the result of an 

 instinctive sense of and craving for a well-ordered ornamentation. 

 In other words, I consider the bird has a marked aesthetic sense, 

 and adduce these facts in support of the theory {vide Emu, June, 

 igog, pp. 236, 237, and Plate XXIII.) To complete the account 

 of my observations on this subject I give illustrations in Plate IX. 

 herewith. Thereon will be found, in sets of three, the three species 

 of leaves most commonly found in the play-grounds which I 

 examined. No. i is Cryptocarya inackinnoniana, F. v. M. ; 

 No. 2 is Litsea dealhata, Nees. ; and No. 3 is Tarrietia argyrodendron, 

 Benth. The illustrations marked A, B, and C show the upper 

 sides of these three species, and the other two illustrations of each set 

 display their lower surfaces or under sides. The remaining 11 of 

 the 14 species will be found illustrated in Plate X., the under 

 sides only being shown. They are as follows : — No. 4, Aleiirites 

 triloba, Font. ; 5, Phaleria neumanni ; 6, Cryptocarya (sp.) ; 

 7, SterculiacecB (sp.) ; 8, Castanospora alphandi, F. v. M. ; 

 g, Coccidus moorei, F. v. M. (two leaves) ; 10, Ruhiacece (sp.) ; 



