CLASS. Acotyledones I. { Stamina hypogyna II. Monocotyledones { perigyna III. { epigyna IV. { { Stamina epigyna V. { Apetalae { perigyna VI. { { hypogyna VII. { { Corolla hypogyna VIII. { Monopetalae{ perigyna IX. Dicotyledones.{ { epigyna { antheris connatis X. { { { distinctis XI. { { Stamina epigyna XII. { Polypetalae{ hypogyna XIII. { { perigyna XIV. { Diclines irregulares XV. This table shows that Jussieu did not oppose the Cryptogams, which he calls Acotyledones, to the whole body of Phanerogams, as Ray did under the name of Imperfectae; he rather regards the Acotyledones as a class co-ordinate with the Monocotyledones and Dicotyledones; but this mistake or similar mistaken views run through all systematic botany up to 1840; the morphology founded by Nägeli and by Hofmeister’s embryological investigations first showed that the Cryptogams separate into several divisions, which co-ordinate with the Monocotyledons and Dicotyledons. At the same time the use of the word Acotyledones for Linnaeus’ Cryptogams shows that Jussieu overrated the systematic value of the cotyledons, because, as is seen from the introduction to his ‘Genera Plantarum,’ he was quite in the dark on the subject of the great difference between the spores of Cryptogamic plants and the seeds of Phanerogams. His conception of the organs of generation was essentially that of Linnaeus; hence he judged of the Cryptogams according to the scheme of the Phanerogams, and, not perceiving their peculiarities, he virtually characterised them by negative marks. If we notice in the above table how the Phanerogams are separated into classes, it strikes us that the triple division into hypogynous, perigynous, and epigynous is repeated no less than four times; this shows that Jussieu had mistaken ideas of the value of these marks for classification, whereas the recurrence of them so often should of itself have suggested a doubt on this point. To judge of his system more exactly we must here give his series of the families, which he had already raised to the number of a hundred. Class I. 1. Fungi. 2. Algae. 3. Hepaticae. 4. Musci. 5. Filices. 6. Naiades. Class II.