Botany. 79 



III. Botany. 



1. Professor van Tieghetn's new System of Classification of 

 Phamogamia. — Those who have watched the recent tendencies in 

 systematic Phgenogamic botany will not be wholly surprised to 

 receive a proposition to change the values of some of the charac- 

 ters depending on the structure of the seed, and to base thereon 

 an attempt at the partial reclassification of flowering plants. 



In Comptes Rendus, May 3, 1897, Professor tax Tieghem of 

 Paris offers for consideration a new system for the classification 

 of Phanerogams, based on the ovule and the seed. For this sys- 

 tem, previous papers in the same periodical, beginning with that 

 for March 22 of the current year, and in the Bulletin of the 

 Botanical Society of France, for a much longer time, have been 

 preparing the way. 



Reserving for a later notice a more detailed account of the 

 principal features of this new system, it is sufficient, at present, to 

 call attention to its revolutionary character. It removes many old 

 landmarks and obliterates many dividing lines, brings about the 

 partial re-arrangement of established genera, placing them in new 

 families, and, in general, initiates a new order of things. One's 

 first impulse is to minimize the significance of the new characters, 

 and to reject the basis proposed. But on careful investigation of 

 the grounds of the new system, especially when such investigation 

 keeps in mind the work by J. G-. Agardh, in 1858, on somewhat 

 similar lines, it becomes clear that the new system is likely to 

 challenge wide attention, and that its claims are sure to be heard. 



In the first paper of the recent series, the author, after briefly 

 stating modern views relative to the gametes involved in fertili- 

 zation, calls attention to the sequence of phenomena which, follow- 

 ing fertilization, culminate in the production of the " fruit." 



Fruits, at their maturity, are of two sorts, one of which has 

 hitherto, in some of its phases, escaped notice. Most frequently 

 the fruit bears (on its outer surface in the case of Cycads and 

 Conifers, on the inner surface of a closed cavity in the case of all 

 other Phanerogams) one or more distinct bodies which can be 

 easily detached, or which may even become detached spontane- 

 ously, when the fruit is ripe. Each of these bodies, formed of an 

 embryo, accompanied or not by albumen, and enveloped by its 

 proper integuments, constitutes what everybody calls a " seed." 

 On its germination, the seed produces a new plant. Most phanero- 

 gams have a fruit provided with seeds, tin fruit semine. Some- 

 times, on the contrary, the fruit neither bears nor contains any 

 such free body which can be separated at maturity. In these 

 latter cases, the whole is in one piece which must be planted as a 

 whole in order to obtain by germination the new plant. Such a 

 fruit is devoid of seeds, un fruit insemine. On this difference, 

 the author divides all Phanerogams into two classes, termed 

 respectively Seminees and Inseminees. The first of these two 

 primary groups is evidently more highly developed than the 

 second. Each of these groups is next divided by the author on 

 the basis of differences in the ovule. 



