HELIOTROPISM—LIST 
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their wings fully expanded, but sometimes close them only to open 
them again. Most often they orient, but sometimes imperfectly; 
one was seen to adjust itself. 
Nissanga patnia, Moore. This butterfly settled with its wings 
up (one exception) and, so far as I observed, with the eye-spot exposed. 
In the majority of cases it oriented. 
Neptis jurnba, Moore; N. varmona , Moore; and Rahinda sinuata, 
Moore. These three species may be conveniently taken together. 
They all have the same gliding flight and all settle most frequently 
with the wings fully expanded, though often closed. As regards 
orientation less than half the specimens observed appeared to pay 
any attention to the direction of the sun’s rays, though one varmona 
was certainly seen to adjust its tail to the sun. 
Castalius rosimon , Fabr, Two specimens seen to orient with 
wings up. 
Observations in England. 
Argynnis papilla, Linn. Mortehoe, 1907, and later. I have 
several times seen this butterfly orient. 
Lycaena corydon, Fabr. Berkshire Downs. I once saw this 
orient. 
Lycaena icarus , Rott. Mortehoe. The constant habit of this 
species is to orient with the fore-wings set further from the hind- 
wings than in most butterflies. 
Hesperia malvae, Linn., and Thanaos tages , Linn. Both orient 
habitually. 
§ 9. “List” and Shadow. 
“ List ” may be exactly defined as an attitude resulting from a 
rotation of the insect about its longitudinal axis, as heliotropism 
results from a rotation about an imaginary vertical axis at right 
angles to this. Heliotropism corresponds to the movement of a 
vessel in answer to the helm. Most vessels, independently of wind, 
waves, or tide, have a tendency to lean somewhat to one side or the 
other; this inclination is termed by sailors “ a list,” and, although I 
am aware that the analogy is not quite close, since the insect may 
lean at one moment to one side, at another to the other, I shall for 
brevity term such an inclined or tilted position a list. 
So far as I know, this list was first observed by Col. C. T. 
Bingham, in 1878, in a Melanitis , but the observation was not 
