78 [SUMMARY OF CURRENT RESEARCHES RELATING TO 



Langdon made the important discovery that carbon monoxide is 

 present in the bladder of Nereocystis, in varying quantities ; but carbon 

 dioxide is rarely present, and in minute quantity. This carbon monoxide^ 

 as the anhydride of formic acid, may well have a bearing on the 

 theories of photosynthesis, and may occur more generally in plant 

 tissues than has been supposed. 



Marine Algae of the Danish West Indies."' — Under this title F. 

 Borgesen continues the work begnn some time ago before the sale of 

 the islands, which he feels very grievously. The last pages of Squa- 

 mariace^ are followed by the treatment of Melobesiea? by Madame Paul 

 Lemoine. After an introduction, in which she discusses the distribution) 

 and affinities of the species collected by Borgesen, she gives a key 

 of the genera and species which amounts to a synopsis. This is 

 followed by a full description of each species, with many text figures. 

 The treatment of the Corallinefe is continued by Borgesen, who' 

 then begins Ceramiales, which is carried into the sixth sub-family,. 

 Spyridie^. The work is interspersed with numerous drawings of the 

 structure of the species de_scribed. 



Japanese Marine Algae.f — K. Yendo publishes Part VII. of his 

 Notes on Algte new to Japan. He records twenty-five species, adding 

 important and enlightening notes to each on synonomy, geographical dis- 

 tribution, and structure. Bryopsis corticuJans Setch. is reduced to a 

 form of B. plumosa, as forshadowed by Setchell in his original descrip- 

 tion, the rhizoidal cortication in the genus being possibly indicative 

 more of a state of robustness of an individual plant than of a specific 

 character. Chsetomorpha antennina Kiitz. is now truly recorded from 

 Japan, the original record by Martens having proved to be erroneous. 

 It occurs on the Bonin Islands. Boodha sianmisis also occurs there, 

 and makes the third out of five known species to be recorded from Japan. 

 Under Sargassum Smidei the author discusses the duplicated or turbi- 

 narioid leaf found in that species, and in S. dupUcatum and others, and 

 so closely resembling the turbiuarioid form in the genus Turhinaria as 

 to suggest a link between the genera. The result of a study of -S'. Sandei 

 shows that the degree of duplication in that species (1) is gradual in a. 

 range of species ; (2) differs according to the stages of development of 

 the thallus ; (3) varies according to the parts of the thallus ; (4) differs 

 according to the sex of the plant. Male plants have, as a rule, luxuriant 

 foliage, and poorly, or not at all, duplicated leaves. Gracilaria lingva, 

 only recorded in a few specimens from the Arabian Sea and from Amoy 

 and now from the Bonin Islands, may possibly represent a state of 

 G. corticata, a variable species. 



* Marine Algffi of the Danish West Indies. III. Rhodophycese. Copenhagen : 

 (1917) pp. 145-240 (figs. 149-230). 



t Bot. Mag. Tokyo, xxxi. (1917) pp. 183-207 (figs.). 



