introduced as a substitute for the bear. It will be observed that the
account of the dragon in the Siward story suggested the further
development of the story in the _Hrólfssaga_. Olrik says: "I én
henseende bar Sivard den digres kamp dog noget eget. De almindelige
norröne dragekampe lige fra Sigurds drab på Fåvne har stadig til mål at
vinde dragens guld. For Sivard digre eksisterer dette motiv ikke; han
vil frelse de hjemsögte mennesker. Af alle de islandske dragekampe har
kun Björn Hitdölekæmpes noget tilsvarende, og her er det næppe
tilfældigt at også den er henlagt til de engelske farvande. Det er det
engelske dragekamps-motiv".[52] Olrik further calls attention to the
fact that in English tales the object is not to kill the dragon, but to
drive it away, as Siward did. But to fit the dragon into the Bjarki
story, it had to be killed in order that the blood-drinking episode
might be introduced. This involved no difficulty, however; for the
killing of the dragon was in harmony with Scandinavian saga-usage. But
it should be observed how, in essence, the conception of the dragon in
the Bjarki story harmonizes accurately with that in the Siward story.
The king and his court are afflicted by the visitations of a dragon; and
Bjarki puts an end to this affliction by killing the dragon, as Siward,
in the corresponding situation, does by driving it away.

Not less terrible than dragons, but much more common, were trolls; and
this fact led Brynjulfsson to remark that the introduction of a troll in
this connection was as characteristic as anything could be.[53] The
introduction of the troll is quite in harmony with the genius of Old
Norse folk-lore. The saga-man did not, however, characterize the dragon
as a troll merely because he would thus be employing good saga-material,
but because the depredations ascribed to the dragon in the Siward story,
which were quite foreign to the accounts of dragons in Scandinavian
folk-lore, were very suggestive of the depredations ascribed to trolls,