Fifteenth and Sixteenth Centuries 69 



professor of natural history and medicine in the University in 1555 

 and also city physician. He was a great lover of high mountains. 

 Despite professional duties that finally led to his death from plague, 

 he translated and edited the Natural History of Aelian and wrote 

 the Bibliotheca Universalis (1545) , a catalogue with titles of all 

 known writings in Greek, Latin, and Hebrew, and his own Historia 

 Animalium (1551-1558) , a natural history in five parts. 



The fourth volume of the Historia Animalium appeared in 1556. 

 A reprint, Liber IHI, qui est de piscium et aquatilium animantium 

 natura, appeared from Zurich in 1558. It describes chiefly fish but 

 contains many invertebrates among the fish proper, all arranged 

 alphabetically and based largely on Rondelet, whose books on 

 " fishes " were published in 1554 and 1555. The " pulmo marinus," 

 the " penna marina," the " pholade concha," the " ungue seu dacylo " 

 and the " ungue seu solene " are mentioned as luminous and figured 

 as woodcuts. Concerning the sea pen, Gesner wrote: " Noctu 

 maxime splendet, stellae modo, ob candorum et laeuorum, haec ille." 



Concerning: the " solene mare," the statement is: " His natura 

 in tenebris remoto lumina, alio fugore, clarere, et quanto magnis 

 humorem habeant." The figure shows a razor clam, Solen, which, 

 together with Pholas, was considered to be luminous by Rondelet 

 and by all the sixteenth-century writers. The mistake is a curious 

 one, possibly based on observation of dead Solen shining from 

 luminous bacteria, or possibly based on Pliny ,who described Pholas 

 dactylus under several names, including Solen. Nearly two cen- 

 turies later, Reaumur (1712, 1723) emphasized the fact that Solen 

 did not luminesce, whereas Pholas did, and that Pholas light was 

 brighter the fresher the animals. 



At the time of his death, Gesner was working on a companion 

 volume to the animal book, dealing with plants, but only scattered 

 botanical writings appeared (1541) . They were finally collected, 

 together with 1,000 drawings, as the Opera Conradi Gesneri, etc., 

 published at Nuremberg in 1751-1772. 



Most of Gesner's Latin writings have appeared in second editions 

 and some have been translated in German. His book on luminescent 

 phenomena, generally referred to as De Lunariis, was reissued at 

 Hafnia (Copenhagen) in 1669, bound together with a second edition 

 of Bartholin's De Luce Animalium, first published in 1647, but with 

 the title changed to De Luce Hominum et Brutorum. With the 

 exception of essays on the phosphorescent Bolognian stone, Bar- 

 tholin's book (1647) was the second publication wholly devoted to 

 luminescence and the works of Gesner and Bartholin remained the 



