Albrecht von Haller

(1708–1777) [Hall.]

This Swiss botanist and physiologist sought a comprehensive taxonomy. While Haller rejected the simplicity of Linnaeus’ system, Linnaeus drew frequently from Haller’s work on cryptogams.

Right: HI Archives portrait no. 4a.
When Linnaeus cites Hall. helv., he's referring to Albrecht von Haller (1708–1777), Enumeratio Methodica Stirpium Helvetiae Indigenarum (Göttingen, 1742).
(see this image enlarged)
(see this image enlarged)