THE JUSSIEUS AND THE NATURAL METnOD 273 



the other parts furnish, as accessory characters, which avvovncc the co-is fence of 

 the preceding, whose minuteness or situation sometimes hinder them from being 

 remarked. It is thus that, among animals, the external disposition of the [»art3 

 indicates the number of ventricles of the heart and other distinctions of the class 

 or genus." Lastly, in his memoir of 1774, be says: "Characters simply general 

 are usually connected with some of the essential characters, a circumstance which 

 affords accessory signs ««wow;?c/w^^ the existence of the true characters ;" and, 

 with reference to the organs of animals, he adds : "He who should content him- 

 self with exterior or secondar}' signs without establishing their affini/ij icith the 

 interior parts, would have but an imperfect idea of the true relations which 

 exist between animals." There is profound analysis in these observations, and 

 equally true whether it be applied to zoology or botany. 



§2 Of classijicatiov. — Let us first consider the classification of Bernard, as 

 stated by M. Laurent de Jussieu : " The orders traced by Bernard in the gar- 

 den of Trianon amount in number to sixty-two, more than half of which are en- 

 tirely conformable to actual families. Several others, likewise conformable, differ 

 only by the addition of strange species which ought to have been detached. 

 Others, still, are a union of several families, which should sometimes remain 

 united, sometimes be more or less separated. The author, having given only a 

 simple manuscript catalogue, without other addition, has not characterized his 

 orders nor assigned the reason of their arrangement. But if we carefully study 

 that arrangement, we first recognize that, without indicating the classes, he has 

 adopted the three great divisions characterized by the embryo. The first orders 

 pertain to the acotyledons, excepting, however, the naiades, which have been 

 separated more recently; and the aristolochia;, which should be completely sepa- 

 rated. In the monocotyledons, which follow, there are seen to appear successively 

 the orders with epigynic stamens, those with perigynic stamens, and those with 

 hypogynic stamens, which proves that he appreciated the characters derived 

 from the insertions. In the dicotyledons he pursues the same course, the same 

 distinction, though concluding with the perigynic plants, and referring to each 

 the monopetalous, pulypetalous, and ap>etalous plants, which have the same 

 insertion, sometimes intermingled, sometimes following one another separately. 

 He terminates his series by the amentacece united to the urticece, the euphorbi- 

 ocece and the conifer ce. It will be seen that, without having proclaimed the 

 natural laws, he has almost always silently obeyed them." (Article Methode 

 naturelle of the Diet, des Sciences Katurelles ) 



Bernard, then, had established sixty-two orders or Xi^l\xx?iS. families; and hav- 

 ing done this, he had united these sixty-two orders into seven classes. "The 

 animal kingdom" says Laurent in his memoir of 1774, "has but seven classes ; in 

 following the divisions of Trianon we count no more in the vegetable kingdom." 

 This number of seven results in effect from the employment of the insertion of 

 the stamens alone for the subdivision of the monocotyledons and the dicntyledons. 

 We have, then, three classes for the monocotyledons, three for the dicotyledons, 

 making six; the acotyledons, left undivided, because their flowers, so little 

 apparent and little known, form the seventh. Laurent felt the necessity of mul- 

 tiplying these classes, and. availing hfmself of the corolla, (a resource which 

 Bernard denied himself,) raised their number first to fourteen, and then to fifteen. 

 "The author of the order of Trianon," he says, "regarding this work as proper 

 for botanists alone, as an advance towards perfection, and a simple indication of 

 the route which should lead to it, desired that, to satisfy the present object, 

 which is that of public instruction, M^e should labor rather for learners than for 

 I adepts; that, without deviating from the true principles, we should seek to 

 I establish a method which should have the classes in greater number, more pre- 

 Ij cise, and consequently more easily to be apprehended. He thought, farther, that 

 'I it was incumbent on him to comply, as far as possible, with the received preju- 

 dice which regards as the preferable method that which is founded on the parts 



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