A CONTRIBUTION TO OUR KNOWLEDGE OF 

 SPLACHNIDIUM 

 CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 220 



Mabel Lewis Roe 

 (WITH PLATES XIV-XVIII) 



Introduction 



Splachnidium rugosum Grew is a monotypic genus of more 

 than ordinary interest because investigators have placed it in 

 one group or another according as some particular feature seemed 

 more worthy of emphasis. The earliest mention of this plant was 

 by Linnaeus (9) as Viva rugosa; a few years later Suhr (18) de- 

 scribed it as Dumontia rugosa; and in 1830 Greville (3) founded 

 the genus Splachnidium, retaining the specific name already given. 



Most authors have placed it with the Fucaceae, but in 1892 

 Mitchell and Whitting (10) published an account which was 

 incorporated in 1895 by Murray (ii) in his book. This account 

 includes the morphology of both vegetative and reproductive 

 tissues. As a result of their investigations, these authors felt 

 justified in establishing a new family, making the following state- 

 ment (p. 9): "The sum of the characters of Splachnidium so 

 expressly excludes it from any existing natural order that there is 

 no other course open to us than to establish one for its reception 

 • under the name of Splachnidiaceae." Kjellman's account (6) 

 restored it to the Fucaceae; and in 1904 Oltmanns (13) placed 

 it with the Ectocarpaceae under the subgroup Encoelieae. 



The material for this investigation was secured by Professor 

 Charles J. Chamberlain at Glen Cairn, near Cape Town, South 

 Africa, on February 28, 1912. A second collection was made at the 

 same place on August 30, 1914, by Miss Edith Stephens of South 

 African College, Cape Town, and sent to Professor Chamberlain. 

 The work was undertaken with the hope of determining (1) the 

 nature of the contents of the reproductive sacs, whether zoospores 

 or gametes; and (2) the origin of the so-called "apical cell," a 

 Botanical Gazette, vol. 62] [400 



