on South American BuiterJUes. 7 



takes. The system of separating after all leads to less confusion; 

 for instance, some of our friends considered Megacephalu cniciata 

 and iM. bifasciata as one species, but how beautifully distinct they 

 are in reality, when we know the fact that M. cruciata is confined 

 to the Lower Amazons, or as far as Barra inclusive, and M. bifas- 

 ciata to the Upper Amazons, all the hundreds of individuals I 

 have met with offering the same points of difference respectively ! 

 Lyynnas vilula is very common along the alleys in the forest at 

 Ega in the showery seasons, June, July, November, January. 

 The only other locality in which I have met with it is Areyros, 

 on the Tapajos, but all the individuals found there are different in 

 colour from the Ega ones. 



The beautiful Zeonia, of which I sent you a fine series last 

 July, I met with in a part of the forest near Ega, which 1 had 

 traversed and examined before, many times, in all seasons. The 

 first specimen I found was a straggler in a different part of the 

 forest. On July 21st, after a month of unusually dry and hot 

 weather, in ascending a slope in the forest by a broad pathway 

 mounting from a moist hollow, choked up with monstrous arums 

 and other marsh plants, I was delighted to see another of what 

 had always been so exceedingly rare a group of butterflies ; it 

 crossed the path in a series of rapid jerks, and settled on a leaf 

 close before me. Before I had secured it, I saw another, and then 

 shortly after a third. I mounted to the summit of the slope, fol- 

 lowed a branch pathway which led along the brow of the ridge, 

 without seeing any more, but returned again to examine well the 

 exact spot where I had captured the three, for it very often 

 happens that a species is confined to a few square yards of space 

 in the vast forest, which to our perceptions offer no difference 

 throughout its millions of acres to account for the preference. I 

 entered the .thicket from the pathway, and a few yards therein 

 found a small sunny opening, where many of the Zeonia were 

 flitting about from one leaf to another, meeting one another, 

 gamboling and fighting ; their blue transparent tinge, brilliant 

 crimson patch and long tails, all very visible in the momentary 

 intervals between the jerks in their flight. I was very busy, you 

 may imagine, at first in securing a supply of specimens ; I caught 

 perhaps 150, two-thirds of which fell to pieces in the bottom of 

 the net, so fragile is their texure. 1 then paused to look around 

 the locality, and endeavour to find the larvae and pupae. I walked 

 through the thicket in all directions, and found the space peopled 

 by the species was not more than from twenty to thirty square 



