(Gy besa) 
and markings very faint or altogether absent ; and, in addi- 
tion to these, specimens holding an intermediate position be- 
tween them as regards the characters mentioned. Dr. Dixey 
exhibited this series (with some additions and substitutions) 
at the Society’s meeting on December 7th, and explained 
that, in order to meet the possible objection that the varia- 
tions in question pointed to local forms, he had been careful 
in the case of each species to select examples from the same 
locality. The species concerned were C. vurina (Mexico), C. 
neocypris (South Paraguay), C. argante (Brazil), C. agarithe 
(Mexico), C. senne (Guatemala and Brazil), and C. philea 
(Guatemala). There was no sufficient evidence as to the 
seasons of appearance of these variations, only seven examples 
(four C. argante and three C. senne) in the whole series 
bearing dates of capture; but the nature of them, and the 
parallelism with which they were displayed by each of the 
six species, were such as to leave little doubt of their being 
seasonal. 
I am further indebted to Dr. Dixey for the first indication 
of the occurrence of seasonal dimorphism in Australia, afforded 
by the Old-World section (Catopsilia) of the same genus Ca/l- 
lidryas. In one species, C. gorgophone, from Melville Island 
and Queensland, gradations are found quite in correspondence 
with those observed in both Indian and Neotropical - species ; 
and the same phases are even more completely illustrated in 
a fine series of Brisbane examples of the well-known Oriental 
C. crocale, which lends some probability to Dr. Dixey’s sus- 
picion that C. crocale and C. pomona (including C. catilla) 
will prove to be seasonal forms of one species.* 
In bringing to a close this attempt to give a general survey 
of what has been published on the subject, 1 purposely abstain 
* ©. crocale is an extremely variable and very widely distributed 
butterfly. Mr. de Nicéville (‘‘Gazetteer of Sikkim,” 1894, p. 166 ; and 
‘¢ Journ. Asiat. Soc. Bengal,” lxiv, ii, p. 490, 1895) considers that C. 
catilla cannot be held a distinct species from C. crocale, all the supposed 
distinctive characters proving quite inconstant, and breaking down when 
large numbers of specimens are compared. But he does not think seasonal 
dimorphism comes into play here, ‘‘ the innumerable varieties which are 
found in both sexes occurring at all times.” 
