THE JUSSIEUS AND THE NATURAL METHOD- 259 



The last letter of Linnoeus bears the date of March 1, 1763. lie had just 

 been named one of the eight foreign associates of our Academy, and says: "Of 

 all the academic titles I have received, none has flattered me so much as tliis, 

 with which I alone, of all my countrymen, have as yet been invested." On 

 Bernard's part the coi'respondence had stopped much sooner; his last letter 

 bears the date of 1751; a subject of no little regret, for it yra,s towards this 

 period that he made, at Trianon, the first trial of his natural orders. He would, 

 without doubt, have said something to Linnaeus on the subject, and however 

 brief his communication, it would now bo of much interest. 



§3. — On Bernard de Jussieu^s mode of ohserinng in botany. 



It is my good fortune, due to the kindness of Dr. Tessereau,* to be now able 

 to add to the memorials already considered sixteen letters of Bernard ; a number 

 which, after what has been said, would seem almost incredible. But the explana- 

 tion is not difficult : between Bernard and a certain M. Artur, a member of the 

 higher council of Cayenne, to whom the letters are addressed, there runs, 

 throughout the correspondence, an incessant exchange of reciprocal solicitations. 

 Artur constantly urges Bernard to procure an increase of his appointment, which 

 seems to have been scanty, and Bernard, as ceaselessly, presses Artur to send him 

 plants and other objects of natural history. In an early part of the correspond- 

 ence Bernard, under date of December, 1736, writes as follows : " You know 

 that the seeds of all the plants of the colony interest us ; I hope that y on will be good 

 enough to collect them for us, as time and opportunity permit. Pray do not neg- 

 lect to send us roots of the simarouba, as well as branches charged with leaves 

 and dried between paper, and the ripe fruit of that shrub ; skilful as you are in 

 drawing, you might sketch for us the flower it bears ; and you are highly com- 

 petent to give its description, with that also of the pareira brava, the ipecacuanha, 

 and other plants recommended by their virtues in medicine or use in the arts." 



Apparently Bernard's estimate of Artur's competency must have undergone 

 some modification, for in the fifth letter he takes the trouble to compose for his 

 guidance a very brief and yet complete treatise of elementary botany, taking 

 care, at the same time, to spare, as far as possible, the sensitiveness of his cor- 

 respondent. 



" Exactness, in the description of all the parts which constitute flowers, be- 

 comes," he says, " more and more necessary for the perfection of the method 

 which arranges plants in classes, and distinguishes essentially each species; we 

 should not adhere solely to the fonn of the petals, and the pai't which, in the 

 flower, changes into fruit ; it is necessary to particularize the figure of the calyx. 

 its composition, the different figure of the petals, the part they occupy, their 

 number, their division, the number of the stamens ; whether they stand alone 

 and distinct, or whether, united in several bodies or a single one, they spring 

 from the sides of a calyx or a petal. The pistils are sometimes single and some- 

 times many in the same flower ; and tliere are three parts to be considered in 

 them, the lower, which is the ovary, the middle, which is the style, and the upper 

 and last, which is the stigma." 



Everything in this little treatise is worthy of remark, for, in indicating to M. 

 Artur the mode of observing, Bernard, at the same time, indicates the scrupulous, 

 attentive, and complete manner (and for the first time complete in botany) prac- 

 ticed by himself. I think it proper, therefore, to reproduce the whole letter : 



"These parts are not always found in the order in which 1 mark them ; in that 

 case, great attention is to be paid in observing the fact ; these parts, too, are often 

 multiple — that is to say, there are several ovaries, several styles, and several 

 stij^mas ; again, their figure, situation, porportion, vary, and all this requires de- 

 tails ; finally, the ovary becomes the fruit, either naked or enveloped, simple and 



* An emiuent physician and author of a valuable treaties on hygiene. 



