(cory 
similarly transformed in appearance. Thus the Uganda form 
of P. sylvia, 3, closely resembled J. spica, ¢, from the same 
region, both being white butterflies with a dark apex to the 
fore-wing, a row of marginal black spots on the hind-wing, 
and a basal patch of bright orange. In the representative 
forms from the Congo region, P. perlucens, Butl., g, and M. 
asphodelus, Butl., 3, the basal orange was in each case replaced 
by lemon yellow. Again, in the West African specimen 
shown of P. sylvia, ¢, the basal orange took on a darker tinge 
and was somewhat modified in shape, in both of which respects 
it came into close correspondence with MM. bernice from the 
same locality. The facts might lend some apparent colour to 
the view that the correspondence was due in each case to 
similarity of surroundings. The speaker, however, thought 
that the difficulties in the way of such an explanation were 
insuperable, and that the relation was in every case mimetic. 
It would not be easy to say whether the mimicry was of the 
Batesian or of the Miillerian kind, the data being scarcely 
sufficient ; he inclined personally to the belief that it would 
prove to be of the latter, 7. e. the Miullerian sort, especially as 
there appeared to be indications of a diaposematic exchange 
of characters between the two series of forms. 
He regretted that the Hope Collection possessed no speci- 
mens of P. nyasana, Butl., 3, for this form together with 
M. riippellii, Koch, 3, would have made a striking addition to 
the exhibit. He should have preferred also to put a specimen 
of the West African P. isokani, Grose Smith, 2, beside the J/. 
poppea, 2, from Ashanti, had one been available. 
Though he had on the present occasion confined himself to 
[xx 
the parallelism existing between these two genera, he wished 
also to remark that in many cases the actual forms shown 
formed part only of a much larger mimetic association. 
Papers. 
Among the papers communicated was :— 
“Studies in the TZetriginx (Orthoptera) in the Oxford 
Museum,” by JosepH L. Hancock, M.D., F.E.S. 
