14 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I3I 



join her. Developments which took place in the next few minutes 

 were unexpected. 



Coition. — The pair had been nest building for at least 2 weeks 

 when they perched together on the termite mound. There was a 

 touching of bills, and the male acted as though he were trying to give 

 her a few extra pellets, but he apparently had none to give. At 

 9:15 a.m. the female flew from the termite nest, closely followed by 

 the male who made a loud, wailing noise. The two headed toward 

 the nest tree, but lighted on a branch at the forest edge. I had to run 

 across the clearing for a better view. Within this short time the male 

 had mounted the female. He came off a few moments later. Then he 

 mounted on her back again, without hurry, and got securely placed. 

 There was no noise. She had her tail held way over to one side. When 

 he mounted he pressed his tail downward and somewhat under her 

 body. His wings were kept closed. After some moments he got off 

 and flew alone to the rim of the nest. She continued to hold her tail 

 to one side. I could see against a background of white feathers that 

 her vent was extroverted but was retracted shortly afterward. From 

 at least 9 45 a.m. until 12 :30 p.m. the female apparently worked from 

 inside the nest on the wall, as she had on previous mornings. 



Gathering of dirt at other nests. — At 5 p.m. on November 7 I was 

 watching nest construction by a pair of hornbills in the Botanical 

 Gardens. The male flew toward me and lighted on the ground 35 feet 

 away. Here he picked up 15 or more chunks of earth. After he had 

 flown away, I examined the spot which proved to be a low termite 

 mound. Freshly opened tunnels showed where the bird had been 

 working. Although hornbills appeared to be especially attracted to 

 termite nests they are not invariably so. Sometimes they pick up 

 ordinary dirt. On October 31 the male from nest 4 lighted on a stick 

 close to the ground of a native shamba. He repeatedly bent over, took 

 up chunks of black cultivated soil, and swallowed them. His next 

 move was to an adjacent banana tree. Here he tore off pieces of leaf 

 and bark, i to 2 inches long, three of which he swallowed. His subse- 

 quent flight to the forest led to the discovery of his nest hole. The 

 wall of this nest was unusually black. 



Construction of the nest zvall. — At various times I watched four 

 pairs of hornbills constructing their nest walls. There was variation 

 in the time of day when work took place. Three pairs worked in the 

 morning and one pair, from the Botanical Gardens, late in the after- 

 noon. Experience at nest 2 was typical. On October 24, the male 

 returned to his tall, isolated nest stump at noon. He leaned over the 

 nest opening as he heaved up pea-sized pellets of dirt. These he 



