1176 THE AUSTRALIAN NATURALIST. 
and adding weights until the pyramid gave way. The weight 
required was somewhat variable with different individual 
blossoms, ranging from 25 to 60 grammes, the average of 
seven trials being 40 grammes, or about 1 1/3 oz. 
Mr. Fletcher has placed on record (Proc. Linn. Soc., N.S. 
Wales IX., 1894, p. 363) the trapping of hawk-moths by 
this plant. 
Other exotic plants having similar floral structures, and 
which when introduced to this country prove fatal to indi- 
genous insects, are /éhynchospermum jasminoides, Lindl., an 
Apocynaceous plant from China, and Arujia sericifera, Brot. 
(Syn. A. albeus, G. Don. and Physianthus “albeus, Mart.) 
belonging to the Asclepiadeae, a native of South America. 
The trapping of an indigenous flower-frequenting Tabanid 
fly by J. jusminoides, which is not uncommon in gardens 
about Sydney, 1s recorded by Mr. Fletcher (Proc. Linn. Soc. 
N.S. Wales, VIII., 1893, p. 45). Some years ago Mr. A. G. 
Hamilton gave me specimens of the flowers of A. sericifera 
grown ab Mount Kembla, which had trapped various butter- 
flies and other insects. Specimens are exhibited which had in 
this way caught the following butterflies: Junonia villida, 
Pardaona flavovittuta, Zizera labradus, Hesperilla compacta, 
-and a small moth. There was also a common bee, Apis melli- 
fera. The butterflies were identified for me by Mr. Water- 
house. ‘ 
In their native habitats these plants do not appear to 
-act as insect traps, the reason being that associated insects 
have learnt the nature of the flowers and know how to rifle 
them without being caught, while the insects of Australia 
have not acquired this knowledgé. The mechanism of the 
‘stamen pyramids or bundles, is doubtless designed to pre 
vent the access of insects which are unable to effect fertiliza- 
-tion, while offering no obstacle to suitable visitors. Obvious- 
ly trapping insects would ba unfavourable to the plant, as it 
would by blocking the flower, effectually prevent the visit of 
-other desirable insects. : 
“Bull-dog” Ant. Camponotus forcipes, Forel. 
Some time ago I brought under the notice of the Society 
(Aust. Nat. ii, 1911, p. 67) a specimen of this ant which 
through some unknown cause had lost its abdomen and one 
leg, and yet was on active duty guarding the entrance to the 
nest. On another occasion at Leura I noticed an individual 
-of the same species which had also lost the abdomen, which 
had been amputated just behind the first abdominal node. 
The insect was otherwise intact, and when found was run- 
ning with numerous others on the surface of a nest. Micro- 
sscopic examination indicates that the abdomen had been for- 
a. 
