368 A CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



1950; and Gaussen, 1944-1952). The Toulouse school regards Pinus as the most 

 primitive genus in the family. The remaining genera are arranged as follows: 

 (1) Cedrus- Abies, (2) Pseudolarix-Keteleeria, (3) Larix-Pseudolarix, (4) Picea, 

 and (5) Tsuga. Other classifications have been proposed by Yarmolenko (1933), 

 Janchen (1949), and Sugihara (1947). Sciadopitys is often regarded as the rep- 

 resentative of a family of its own (see Janchen, 1949; Takhtadjan, 1950; Johan- 

 sen, 1951). A few authors have proposed the segregation of the family Taxo- 

 diaceae into several independent families (see Janchen, 1949; Sugihara, 1947), 

 while the majority have retained it in its earlier sense — except for the exclu- 

 sion in some instances of Sciadopitys as mentioned above — and instead divided 

 it into several subgroups. There are similar differences of opinion on the clas- 

 sification of the Cupressaceae, and here, too, new families have been proposed 

 (see Janchen, 1949; Sugihara, 1947), w^ile in other cases subfamilies are dis- 

 cerned (H.-L. Li, 1953, etc.). The Podocarpaceae in the usual sense may also 

 comprise genera of widely varying affinities (Buchholz, 1934; Johansen, 1951). 

 These discrepancies are in the main due to our still incomplete and unsatis- 

 factory knowledge of the true affinities of the various conifer genera. 



The class (or order) Coniferae at large has either been classified directly in 

 a series of groups of family rank, or attempts have been made to discern orders 

 (or suborders). Janchen (1949) and Neger, Miinch and Huber (1952) distin- 

 guished the orders Taxales (Taxoideae) and Finales (Pinoideae), thus adhering 

 in principle to the old artificial subdivision of the conifers into the two families 

 Taxaceae and Pinaceae. Gaussen 's (1944-1952) system has three suborders: 

 (1) Taxineae, with the Taxaceae; (2) Podocarpineae, with the Podocarpaceae; and 

 (3) Pinoidineae, with the remaining families. The Podocarpineae and Pinoi- 

 dineae were considered two different evolutionary branches derived from the 

 "paleoconifers." Pulle (1937, 1950), however, has introduced quite a different 

 system for the conifers, including no less than five orders, viz., the Araucariales, 

 Podocarpales, Pinales, Cupressales (with Taxodiaceae and Cupressaceae), and 

 Taxales (with Cephalotaxaceae and Taxaceae). In this system Florin {in H. 

 Erdtman, 1952) has proposed that the Taxaceae be removed from the conifers 

 and raised to the rank of an independent class, and that the Cephalotaxaceae 

 be raised to the rank of a separate order of the Coniferae. 



Taxales 



Sahni (1920) expressed the opinion that the taxads were so distinct from 

 the true conifers that they deserved to rank as a separate phylum, Taxales. Be- 

 sides some studies of gametophytes and embryogeny, contributions toward our 

 knowledge of the taxads have in recent years been made, inter alia, by Saxton 

 (1934) in respect of the reproductive organs of Austrotaxus, by Wilde (1944) 

 of the male organs of Austrotaxus and Amentotaxus, and by Phillips (1941) 

 and Greguss (1951) of the structure of the secondary wood of these genera. Ac- 

 cording to Florin (1938-1945, 1948a 1948b, 1951), the living taxads represent 

 five genera, viz., Taxus, Torreya, Nothotaxus, A7ne7itotaxus, and Austrotaxus. 

 Reproductive organs of fossil taxads have so far only been studied in Paleo- 

 taxus of triassic age and in a Taxus of Jurassic age. Florin found that in certain 

 respects the taxads are clearly apart from the true conifers. In the taxads the 



