THE STEAIT OF MAGELLAN. 249 



that, on the western side of the continent, he never observed 

 it in Chili. I obtained specimens of some fine Crustacea on 

 this occasion, including a Hepatus {H. angustatus), a Lupa 

 (Z. crihraria), with a beautifully mottled carapace, remarkably 

 produced on each side into a sharp spine, and the curious 

 Hip'pa emerita, which burrows in the sand. 



On the 3d, Dr. Campbell and I ascended the lower part of 

 the Corcovado, and spent much time deeply interested in the 

 contemplation of a number of leaf-cutting (Saiiba) ants, which 

 were marching along in armies, each individual carrying a 

 portion of a green leaf, held in its jaws, over its back. The 

 size of the loads carried in many instances was most surpris- 

 ing. I preserved at the time specimens of them ; and the 

 pinna of a leaf which was being carried by a single indivi- 

 dual now lies before me, measuring nearly two inches and 

 a half long, by almost half-an-inch broad ! It was a most 

 curious sight to watch the industrious little creatures cutting 

 semicircular pieces out of large leaves which had been 

 previously detached, and let fall to the ground, by biting 

 through the petiole. There seemed to be two classes of 

 labourers, each with their own special work — one set, with 

 very large jaws, acting as sawyers, while another body, with 

 jaws of smaller size, carried off the loads when they were cut. 

 The rapidity with which they cut out the pieces was also 

 most remarkable, fragments nearly an inch in size being 

 detached in less than five minutes. Another body of these 

 insects observed by us on another occasion, in the public 

 gardens in the city, presented a most curious appearance, 

 marching in single file, each carrying a fragment, from half 

 to three-fourths of an inch long, of the leafy twigs of a Thuja, 

 over its back, so as to recall the celebrated " moving wood " 

 which came to " Dunsinane." 



