THE VOLCANO IRAZU 13 5 



of the mother-crater has disappeared. But to whichever it 

 belongs, It forms a very narrow sharp ridge several hundred 

 feet high, which falls away steeply both to east and west, so 

 that it fully justifies the name of "knife-edge" we gave it 

 both now and in our September visit. Ascending this trail 

 and walking on the top of the knife-edge we were again ex- 

 posed to the strong easterly wind which, bringing mist and 

 rain once more, made traveling very difficult and wet us 

 with uncomfortable thoroughness before we reached our 

 tent again, about 1,30 P. M. 



The rain and mist continued all afternoon and more or 

 less all night; whenever we woke we heard the roaring of the 

 wind over the crater top, but very little reached us in our 

 sheltered nook. It was dark and rainy in the morning and 

 we stayed rolled up in our blankets, as the warmest place, 

 until nearly seven o'clock. At intervals the mist lifted a 

 little, occasionally even leaving the craters quite clear for a 

 few minutes. We employed these intervals in hunting for 

 beetles under stones in the black sand, in making a sketch 

 of the various craters from the rim we visited the first night 

 and in gathering plants for identification. 



The beetles found proved to be three small species of 

 Carabidae, all chiefly black in color. The largest, one-third 

 of an inch long, Amara costaricensis, is shining, with eight 

 striae on each elytron, antennae and legs reddish-brown, 

 the tibiae of the first pair each with two distal spines which 

 are longer and stronger than those on the other legs. An- 

 chomenus lo-punctatus, one-quarter of an inch in length, 

 has a satin-like luster above but is shining below. Its 

 elytra have each eight striae but the legs are black except 

 for the reddish-brown coxae. Bembidium rogersi was the 

 smallest of the three, one-sixth of an inch long, shining, also 

 with eight striae on each elytron but the four striae of each 

 wing-cover nearer the middle line of the body are more 



