Nov., t9o31 THE CONDOR ?45 bushes extended in a narrow belt for about two hundred yards in the otherwise open water and iu them were perched between two to three hundred birds. At our first stop the outstretched necks and changing position of some of the birds gave evidence ot their uneasiness and as we waded still nearer most of them flew clumsily down into the open water. After moving out a hundred yards beyond the line of bushes they formed ablack line on the water where they remained as long as we stayed in the. vicinity. When the birds becanae alarmed at our ap- proach they began a curious guttural grunting which came in a low continuous chorus from those left in the bushes as well as those in the water. These notes sounded much lille the low grunting of a lot of small pigs while feeding. As we waded among .the bushes the birds which had remained by their nests pitched off into the water one after the other and swam out to join the main flock; or took wing, and after a short detour, came circling close overhead, uttering at sho?t in- tervals their guttural notes of alarm or protest. The nests were strong platforms placed on forking branches and measured about fifteen inches across and four to six inches deep with a shallow depression in the top. They were composed entirely of small sticks compactly arranged as is shown in detail in the accompanying photographs. From one to half a dozen nests were placed in a bush and we planted our tripods in the muddy bottom and standing nearly waist-deep in the water secured good pictures before calling up the boat and getting abroad. As the bushes were scattered we had no trouble in poling about and examining the nests at leisure. Most of them were just com- pleted and contained no eggs. Quite a number had a single egg and in a few cases two eggs were found. A series of eighteen eggs were taken. They are rather small for the size of the bird and have a pale green ground color overlaid with the usual chalky white deposit which gives them a greenish white shade. Three eggs representing the extremes of variation out of this series measure respectively (in millimeters) 55.4 by 33.2; 52.2 by 4r.6 and 53 by 34-3- After finishing our inspection of the nests we returned to the large boat so late that the day breeze failed and left us drifting about the lake all night and prevented our reaching town until late the following day. On January 5, r9o3, we made another visit to this nesting place and with the exception of a single young bird recently hatched the nests of the entire colony were absolutely empty, so it was evident that the place had been deserted as the result of our former visit. ' Instead of between 200 and 300 birds which we saw on our first visit not more than fifty were seen this time. The water in the lak? and river was unusually, low this season which may account for the presence o? this unexpected colony, for the native fishermen agreed in saying that these birds only nest in some trees far up the lake shore, and sometimes in large willows along the marshy borders of the Lerma near its outlet in the lake. However that may be? it was a stroke of good Christmas luck that we made this find since the nesting habits of this species appear to be practically unknown so far as I have found in published accounts of the species.
