some Best-attitudes of Butterjlies. 105 



and settled on a reddish sandy path. Cloud came 

 over the sun, and the butterfly closed up its wings, 

 so that only the hind-wing and tip of the fore- 

 wing were visible. 

 In explanation of this note Dr. Dixey emphasizes the 

 fact that in the dry-season form of ione (= speciosus, 

 Wallengr.) the under-side of the hind-wing and the tip 

 of the fore-wing are reddish, hence the tightly-closed 

 attitude is cryptic on red soil. He adds that doubtless 

 when the butterfly contemplates a long stay (as at night, 

 or when the sun goes behind cloud) the closed-up attitude 

 is adopted to take advantage of its cryptic colouring, and 

 not to minimize its shadow. 



The other observations were made on Belcnois severina, 

 Cram., a white butterfly that we found very abundant at 

 Durban. 



Dr. Dixey says : — 



B. severina, ^ and $ ; wdien clouds come over the sun, 

 this species generally settles on a grass stem, and, 

 closing its wings tightly, becomes part of the picture. 

 It certainly generally turns its back to the sun 

 when it settles in sunshine, and then does not 

 often close up its wings. 

 My note is as follows : — 



B. severina, 2 $ seen to settle aovss the sun, early in 

 the day. Late in the afternoon many $ severina 

 seen settled with wings three-quarters open, and 

 tail more or less to the sun ; but where much ex- 

 posed to wind the wings were closed and the head 

 turned to the wind, so as to be almost across the 

 sun. 

 It is worthy of remark that throughout all these 

 observations of heliotropism, I cannot recall a single 

 case in which an adjustment, or subsequent movement 

 of the butterfly after pitching, tended to throw it out 

 of orientation. Hence it is fair to assume that if the 

 insects had been watched longer after pitching positive 

 results would have been observed in a larger proportion 

 of cases. 



But, be that as it may, beyond doubt it is a habit with 

 a number of butterflies, especially Nymphalids, to settle 

 Avith their backs to the sun. Whether they do this, as 

 Professor Parker supposes, to display their charms to the 

 greatest advantage, or whether the first impulse was 



