HISTOKY OF BOTANY. 321 



were celebrated exceptions. The first gave the earliest cor- 

 rect representation of the primitive form of the spiral vessels ; 

 (Diss, de Vasis Plantarum Spiralibus, Leipsig, 1758j 4to.) 

 Hilfs Construction of Timber, London, 1770, 8vo. contains 

 good investigations respecting the structure of wood, as also 

 respecting the effects of the absorption of coloured fluids, — ^and 

 it is adorned with good plates. Saussure''s Observations sur 

 PEcorce des Feuilles et des Petales, Geneva, 1 762, contains the 

 first correct researches respecting the slits. Nor must we forget 

 the excellent researches of Charles Bonnet, tvho died in 1793, 

 respecting the uses of leaves. These were first published at 

 Gottingen, 1754. Above all, however, Henry Ludwig du 

 Hamel du Monceau, inspector of the French Navy, who died 

 1782, deserves to be celebrated as the greatest writer of that 

 period respecting the physiology of plants. La Physique des 

 Arbres is the title of his immortal work, which was published 

 in two volumes at Paris, 1758. 



458, 



Foreign countries were examined, during the time of Lin- 

 naeus, chiefly by his scholars, among whom Frederick Has- 

 selquist, who died 1752; Peter Forskol, who died 1763; 

 Peter Lofling, who died 1756 ; and Peter Kalm, who died 

 1779, deserve particularly to be named. Hasselquist^s Tra- 

 vels in Palestine were published by Linnaeus himself, 1757 ; 

 ForskoPs Flora ^Egyptiaco-Arabica was published by Nie- 

 buhr, at Copenhagen, 1775; Lofling's Travels in the Spanish 

 Dominions of America were published by Linnasus, 1758 ; 

 and Kalm's Travels in North America were published in 

 three volumes, at Stockholm, 1753 to 1761. 



The botanical treasures of Philibert Commerson, the fellow 

 traveller of Bougainville, who died 1773, could be of no ser- 

 vice to Linngeus, because they were deposited with the French 

 Academy, and have been partly employed by Antony Lorenz 

 Jussieu. 



Northern Asia was examined in the most careful manner, 

 during the time of Linnaeus, by Peter Simon Pallas, who 

 died in 1811. His Travels through the various Provinces of 



X 



