( Jom”) 
This species connects the American mimetic species of Cosmo- 
desmus with the non-mimetic ones, and would be an interesting 
object for the study of the wing in the pupa inasmuch as the 
imaginal wing in the pupa might show traces of the cell-bars 
which are so common in Cosmodesmus, but entirely lost in the 
imago of P. asius. 
All the mimetic American Cosmodesmus resemble ‘“ Aristo- 
lochia Papilios”’ of the same country, with the exception of 
P. pausanias, which imitates a Heliconius. In the Oriental 
Region, where ‘‘Aristolochia Papilios”’ also abound, the mimetic 
Cosmodesmus on the contrary all bear the garb of Danainae. 
Such mimetic resemblances are often ascribed to the common 
ancestral pattern being preserved both in the model and the 
mimic. This explanation may be true in some instances, but 
it does not apply to the mimetic Cosmodesmus as a whole, as 
the Eastern Danaine pattern and the very different colouring 
of the American species cannot both be ancestral in Cosmo- 
desmus. 
Like many other mimetic Lepidoptera, the American 
mimetic Cosmodesmus present some interesting cases of poly- 
morphism. We consider the tailed Cosmodesmus of South- 
Eastern Brazil allied to P. lysithous as forms of one single 
species (lysithous, aedipus, rurik, pomponius, etc.), and also 
believe that Papilio protodamas is the same species as chori- 
damas. These conclusions are mainly based on a study of the 
structure. But morphological evidence, though it may afford 
guidance, cannot be accepted as sufficient. The final court of 
appeal in such questions is breeding, and we hope that some 
day some entomologist resident in South-Eastern Brazil will 
give up mere collecting in order to devote himself to the 
elucidation of the life-histories and habits of the Lepidoptera. 
THE ASSOCIATION OF THORICTUS AND MyRMECOcCYsTUS.— 
Mr. CHAMPION exhibited a specimen of Thorictus pauciseta, 
Wasm., attached to the scape of the left antenna of a worker 
of an ant, Myrmecocystus viaticus, F., found by Dr. Santschi 
and himself at Kairouan, Tunisia, last May. The beetle pos- 
sesses a tuft of golden hairs at each hind angle of the pro- 
thorax, the secretion from which is said by Wasmann to be 
appreciated by the ants. Numerous examples of the beetle 
