Noun which may take the genitive case particle 'no', Noun
jam-packed; packed in like sardines
Idiomatic expression
移民たちは、そこへ、木の漁船にすし詰め状態で、危険な航海をするのである。Packed into wooden fishing boats like sardines, the immigrants undergo the dangerous voyage there.
Also written 寿司詰め【すしづめ】、鮨詰め【すしづめ】