HE present Edition o/ Steno comprises all the works of 

 a scientific nature, which are known to exist from his 

 hands. It embraces not only the scientific works, which 

 he himself published (II. IV. V. VI. XIII. XV. XVI. 

 XVII. XXII. XXIII. XXIV. XXVII) and those which 

 he left to others to publish (X. XII. XIX. XX. XXI. XXV. 

 XXVI. XXVIII. XXXI. XXXII. XXXIII), but also those which appeared 

 without his knowledge, such as the Letters to Thomas Bartholin and 

 Cosimo III and his Lecture on the anatomy of the brain (I. HI. VII. VIII. 

 IX. XI. XIV. XVIII. XXIX. XXX). An Appendix has been added, com* 

 prising two fragments of Letters (XXXIV. XXXV) dealing with observa= 

 tions made by Steno, as well as the notes which his pupil, Holger Jaco* 

 baeus, wrote on the dissections and lectures of Steno during the years of 

 1672-1674 (XXXVI). 



In the present Edition the works of Steno are printed in the order in 

 which the researches, forming the basis of the various Treatises, were made. 

 This is, according to the view of the editor, all the more justifiable, as in 

 that manner it becomes possible to follow with ease the course of Steno's 

 researches, while if the Treatises were arranged after their dates ofpubli= 

 cation, works, which were very near to one another in subject and the 

 dates of the researches they record, would have to be placed far apart. 

 An arrangement of the Treatises after their contents would be quite im- 

 possible to carry through, seeing that so many of the Treatises each of them 

 deal with such widely different subjects. 



Below the halfititle of each Treatise have been placed the arms of the 

 town where the researches, which are mentioned in the Treatise, wholly 

 or for the greater part were made, or where the Treatise was composed. 



