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EASTERN ETHIOPIA 
XXVIII 
tail is of great assistance. Darters feed as the sun 
declines, and they are often seen in flocks. I have 
counted twenty roosting on one tree, which, though 
leafless, was white with their guano. 
The skill these birds exhibit in securing fish is as 
amazing as their voracity. The size of the fish it is 
able to swallow astonished me. On the White Nile I 
found in the stomach of a darter three fishes, one of 
wliich was as big as a herring. 
The fish-spearing habit of the darter is aided by a 
peculiar mechanism in its neck. The first eight 
cervical vertebrae, especially the eighth, are modified 
and produce a kink in the neck : correlated with the 
modification of the vertebrae are some powerful muscles 
which enable the bird to make sudden and powerful 
thrusts with its beak when it impales a fish. In order 
to facilitate the retention of the fish after it is trans¬ 
fixed, the edges of the darter’s beak are furnished with 
fine needle-like points directed backwards. 
The stomach of the darter contains, at its pyloric 
outlet, a singular sieve formed of hairs developed from 
the gastric epithelium. The lining of the stomach is 
sometimes shed more or less completely and a new one 
forms. 
Cormorants, insatiable fish-eaters, abound in the 
Victoria Nyanza : they swarm on the shore of every 
island and inlet. Around the Cascades of Jinja 
they are present in hundreds, helping the herons to 
whiten with their guano the rocks and trees in tlie bays 
and recesses around the head of the Nile. 
It is delifi^htful when out on the lake in a steamer, or 
in a canoe, to see cormorants sitting on the small papyrus 
islands which float about Kavirondo Gulf; as the 
steamer approaches, they either fly away or dive 
beneath the surface of the water. Some parts of the 
Suez Canal, especially the lakes, swarm with cormorants, 
and as the ships glide through the water these birds 
often crowd themselves on the light-buoys : it is not 
