252 A YEAR OF COSTA RICAN NATURAL HISTORY 



A not uncommon low plant on this hillside was a palm- 

 like grass with leaves divided into two lobes each ending 

 in an elliptical point and known {teste Professor Tristan) as 

 "cola de gallo" (cock's tail). Two of these cock's tails, 

 of about three feet in height, had curious nests upon them, 

 attached in each case to a leaf. Both nests were inhabited 

 hy small black ants, but the nest-substance resembled that 

 of which termites' nests are formed and the plan was termite- 

 like, although there were no covered passages leading to them 

 as termite nests have. One leaf was so decayed that, soon 

 after I plucked it, it fell apart. It is difficult to understand 

 why nests should be built on so temporary a foundation as 

 a leaf must afford. 



Only a few yards from the site of these nests I caught one 

 of the most ethereal of butterflies (Callitcsra menander). 

 Its wings, spreading two inches, were chiefly transparent 

 and brownish, but each of the hind pair had a blue-black 

 "eye-spot" on the outer margin and a patch of delicate 

 rose along the hind edge. It is of the Satyrine subfamily 

 of the Nymphalidse distinguished by one or more of the 

 veins of the fore wings being swollen at the base. 



On Saturday, August 7, 1909, P. went to Peralta. On 

 my arrival I presented to Mr. B. M. Hess, the station- 

 master, a letter of introduction from Mr. John M. Keith. 

 Mr. Hess (a native of Lancaster, Pennsylvania) took me to 

 his own room in the second floor of the station and placed 

 a cot at my disposal. I had brought a mosquito net with me, 

 under which I slept each night, as I had been warned that 

 Peralta was malarious. In fact, Mr. Hess said that he was 

 suffering from it; he had a net but was not using it, although 

 when I left he was promising himself to do so. Red ants 

 were abundant in our bedroom. I know I picked many from 

 my cot; perhaps they kept other insects away. Mr. Hess 

 inquired if two other kinds of insects had eaten me up; 



