Phylum Rhodophyta [ 47 



3. The auxiliary cells originating after 

 fertilization as branches of the sup- 

 porting cells of the carpogonial 

 filaments Order 6. FLORroEA. 



Order 1. Cryptospermea [Cryptospermeae] Kiitzing Phyc. Gen. 321 (1843). 

 Order Periblasteae Kutzing op. cit. 387, in part. 

 Orders H elmint hoc lade ae J. Agardh Sp. Alg. 2: 410 (1851), Chaetangieae op. 



cit. 456 (1851), and Wrangelieae op. cit. 701 (1863). 

 Order Batrachospermaceae'R.ahtnhovstKxy^X.og.-Yl.^dichstn 1: 278 (1863). 

 Nemalioninae Schmitz in Flora 72: 438 (1889). 



Order Nemalionales Engler in Engler and Prantl Nat. Pflanzenfam. I Teil, Abt. 

 2: ix (1897). 

 Heterocarpea normally without diploid bodies, the carpogonium arising from the 

 zygote or from an adjacent cell serving as an auxiliary cell, the carpospores produc- 

 ing haploid bodies like the original ones. Certain genera which are exceptional to 

 these characters are noted below. Batrachospermum may be regarded as the standard 

 genus. 



In all recent literature, this order is called Nemalionales. Eight families are rec- 

 ognized. The forms consisting of mere filaments, Acrochaetium, Rhodochorton, and 

 others, are family Acrochaetiacea [Acrochaetiaceae] Fritsch (Family Chantransi- 

 aceae Auctt., but Chantransia DC. as originally published included no members of 

 this family; Papenfuss, 1945). In the remainder of the order, the filaments are 

 differentiated, or, with or without differentiation, organized as bodies of definite 

 form, simply cylindrical, branched, or flattened. Fresh-water examples (the only 

 fresh-water Heterocarpea) include Batrachospermum, Lemanea, and Thorea. These 

 organisms are not red, but bluish, green, or brown. Marine examples include Nemalion 

 and Cumagloia. 



In Liagora tetrasporifera and certain other species tetraspores are produced in the 

 place of carpospores. Within this genus, then, there has been a change in the time of 

 meiosis (which could be established, presumably, by a single mutation) from im- 

 mediately after fertilization to the end of the cystocarp stage. 



Galaxaura is a genus of tropical marine algae which are calcified, which is to say 

 that they deposit much calcium carbonate in the tissues; they were originally classi- 

 fied as corals. They have distinct sexual and tetrasporic stages. Svedelius (1942) as- 

 certained their life cycle. Carpospore-bearing filaments arise both from the zygote 

 and from other cells, previously undifferentiated, which serve as auxiliary cells. The 

 genus has the structure of the present order, and is to be placed here, in spite of ex- 

 hibiting in unspecialized form the life cycle of the following orders. 



Order 2. Sphaerococcoidea [Sphaeroccoideae] J. Agardh Sp. Alg. 2: 577 (1852). 

 Family Gigartineae Kiitzing (1843). 



Orders Gigartineae and Chaetangieae J. Agardh op. cit. 229, 456 (1851). 

 Gigartininae Schmitz in Flora 72: 440 (1889). 

 Order Gigartinales Engler in Engler and Prantl Nat. Pflanzenfam. I Teil, Abt. 



2: X (1897). 

 Order Nemastomatales Kylin in Kgl. Fysiog. Sallsk. Handl. n. f. 36, no. 9 : 39 



(1925). 

 Order Sphaerococcales Sjostedt in Kgl. Fysiog. Sallsk. Handl. n. f. 37, no. 4: 



75 (1926). 



