Frederick, a well-known traveller, was a native of East Gothland, and born in the year 1722. He prosecuted his medical and botanical studies at Upsal. Linnæus having represented in his lectures the important advantages which might be gained by travelling through Palestine, which was at that time but little known, Hasselquist felt the fire of ambition burn within him at the declaration of his master. As the crown gave no pecuniary encouragement for undertakings of this description, extensive collections were made by private individuals, especially from the country of our author, and stipends were granted him by all the faculties in the University of Upsal. Protected in this manner, he began his journey in the summer of 1749, and, through the influence of Lagerström, obtained a passage to Smyrna in a Swedish East Indiaman. He arrived at Smyrna about the latter end of the year, and met with the most friendly reception from the Swedish consuls. In the beginning of 1750 he set out for Egypt, and remained about nine months in the metropolis of that country, whence he transmitted to Linnæus some specimens of his researches, which, after they were published, obtained the approbation of the public. By the influence of Dr Wagentin, a collection of ten thousand dollars of copper currency was made for the encouragement of young Hasselquist in the prosecution of his researches. In the spring of 1751, he passed through Jaffa to Jerusalem, and returned afterwards to Smyrna by way of Rhodes and Scio, having completely fulfilled the expectation of his country; but he did not live long enough to reap the fruits of his labours. His lungs were affected by the burning deserts of Arabia; and after languishing for some time in great distress, he expired in February 1752, before he had completed the thirtieth year of his age. An account of his voyage was published by Linnæus, by whom his memory was honoured with a plant which he called *Hasselquistia*.