DIE NATURLICHEN PFLANZENFAMILIEN : ALG/E. 65 



Algariiiii, published in 1896. Many of the figures are original, and 

 others are taken from works not easily accessible to many students. 

 They add largely to the usefulness of this volume. 



The expounding of Prof. Schmitz's new classification of Rhodo- 

 jjliycem has been awaited with interest. In 1889 he published the 

 outlines of it, without explanation, in Flora, and it is only now that 

 phycologists are in a position to criticise the new system in detail. 

 The premature death of this able investigator — nearly three years 

 ago — delayed the publication of his work, but his friend Dr. 

 Hauptfleisch has completed it on the lines laid down by Dr. 

 Schmitz, The FJiodomelecB are dealt with by Dr. Hauptfleisch and 

 Prof. Falkenberg. 



The Fihodophi/ct'fC are divided into Bamjiales aud Floridea, the 

 first containing three natural OTdevs—FhoduchcBtacea, Compsopogo- 

 nacem, and Fhoreace/r. FloridecE is subdivided into four main groups, 

 differing in the mode of development of the fertilized carpogonium. 

 The system of classification hitherto followed was founded by Dr. 

 Agardh on the formation of the mature cystocarp, without regard 

 to its development. The practical difficulties of Dr. Schmitz's 

 system are obvious, for but few plants can be easily obtained in 

 such successive stages of development as to determine into which 

 of these four divisions it falls. Until that point is decided, nothing 

 but previous knowledge of the different genera can possibly be of 

 any assistance. To a beginner in the systematic study of alg«, 

 such a system is discouraging. In some cases the natural orders 

 associated by Prof. Agardh still fall together, and many of them 

 contain the same genera. The relationship of RhodomelacecB and 

 CeramiacecR is recognized, and both orders are placed in the tbird 

 of the four large groups, i. e. FJiodymeniales. Several genera 

 hitherto regarded as belonging to lihodomelacece are banished to 

 other orders, while Laurencia, Cladijinenia, and Coeloclouhim are 

 included in UhodomehicecB. Some new genera are also created, and 

 Harvey's Chondria reappears to take the place of Dr. Agardh's 

 Choiidriopsis. 



In the diagnosis of Gatti/a on p. 499 an odd mistake occurs. 

 The cystocarps are minutely described, and a few lines lower a 

 remark is made to the effect that the position of the genus must 

 remain uncertain, owing to the cystocarps being unknown ! 



In Grateloupiaccm J. E. Gray's Codiopkyllum, referred to above, 

 is revived. It had been sunk by Dr. Agardh into Thamnociunimn 

 Kiitz, but its one species is now separated off again on account of a 

 difference in the cuticular structure. 



Such work as this of Prof. Schmitz has necessarily required an 

 immense amount of minute examination of alga in various stages 

 of development, and it seems a pity that similarity of vegetative or 

 other characters does not play a larger part in the diagnoses of his 

 main groups. The exclusive consideration of one part of any plant, 

 even though it be of such importance as the development of the 

 fruit, is somewhat unsatisfactory ; and it remains to be seen 

 whether the new system is founded on a firm enough basis to 

 stand entirely in its present form. FSB 



