NOTES ON SNAKES IN EAST AFEICA 
825 
among the fallen leaves on the edge of the forest reserve. 
The writer met with it at Kagiado, but nowhere in German 
East Africa, though it has been recorded by others from Tanga 
and elsewhere. 
The widely-distributed Yellow-bellied Sea-snake (Hydrus 
platurus), which inhabits the Indian and Pacific Oceans from 
Australia and India to Panama probably also frequents the 
East African coasts. A comrade while bathing at Dar-es- 
Salaam saw what he took to be an eel, but from his description 
it appears to be more probably this Sea-snake. All sea-snakes 
are highly specialised for their aquatic life, having vertically 
flattened tails with which they propel and steer themselves. 
Their nostrils also are provided with valves enabling them 
to be closed when the creature dives. All the species are 
very poisonous. 
The next division of the Colubridae comprises the back- 
fanged ( Opisthoglypha ) venomous snakes, and, by reason of 
their poison-conducting teeth being situated so far back on 
the upper jaw, it is difficult for them to inflict a dangerous 
bite upon man unless the reptile is of large size. Their venom 
is often highly toxic, in some species approximating to cobra 
venom in its neurotoxic nature ; in others the haemotoxin 
preponderates as in the vipers. 
Whilst searching beneath stones at Longido one frequently 
met with a terra-cotta-coloured snake with a black head ; in 
bulk they were much the same as a lead pencil and did not 
exceed a foot in length; their narrow gape rendered them harm- 
less. At Arusha one night the writer was called up by some- 
one who said that there was a snake in one of the tents in the 
maxim lines. On arrival we found the tent in darkness, and 
no one willing to move. One complained of a snake crossing 
his face, having waked him up, and he absolutely refused 
to move till a light was brought. When an inch of candle 
was at last obtained, and being assured the snake was not 
to be seen, he sprang up quickly, and after a brief search, 
discovered the snake beneath his blanket. It was one of 
these Jackson’s black-headed snakes ( Apparallactus Jachsoni), 
— there are seven species of the genus in East Africa. 
The common South African Boomslang ( Dispholidus 
z 
