ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 305 



here disproved. Cladothele Hook. f. et Harv. is lestored as a genus. 

 The characteristic papilhL' are well figured, and the difference between 

 this genus and Stktijosiphon is clearly shown. In Cladothele the termina- 

 tion of each branch shows an apical cell ; in Stictz/osiphon the growth is 

 trichothallic, each branch ending in a hair — a difference which implies 

 not only different genera but different orders, according to Kjellman. 

 Xotes are given on Adenocytis and Utriculidium, with figures of their 

 structure, and a discussion of their relationship and systematic position. 

 Additions are made to our knowledge of many other genera and species, 

 Myrionema, Stereocladon, Scytothamnus, Lessonia, Macrocysiis, Ascoseira, 

 etc. Two new genera and ten new species are described. The figures 

 are of value. E. S. G. 



Biochemistry of Marine Algse. — H. Kylin {Zeitschr. Phys. Chem., 

 1913, 83, 171-97; see also Bot. Centralbl., 1918, 138, 269-70). An 

 account of some important investigations made in the Medico-chemical 

 Institute at Upsala. Fucosan is that substance which is contained in 

 the fucosan-bases of the Fucoide^e, and is coloured red by vanilla-HCl. 

 Phycophacin is merely oxidized fucosan. When boiled in dilute HoSO^, 

 fucosan splits off no sugar, and therefore does not belong to the gluco- 

 sides. Mannite was found also in Laminaria cloustoni and Pylmella 

 litoralls, but not in the red alga Fnrcellaria fastiyiata. Ascophylhmi 

 nodosum, Fucus vesmdosiis, Laminaria saccharina and L. digitata con- 

 tain simple sugars — dextrose and levulose. Apparently the Floridete 

 contain only traces of these sugars ; but in the Fucoidege they are the 

 first visible products of assimilation. And in the four brown algfe 

 above-mentioned there is a dextrin-like polysaccharide called Laminarin, 

 which is a reserve-material formed by a condensation of the dextrose ; 

 physiologically it corresponds with the starch of the higher plants. As 

 regards Floridean starch, by hydrolysis with dilute acid it yielded 

 dextrose ; when made into a paste with warm water it is quickly con- 

 verted into sugar by malt-diastase, but raw unaltered grains are not 

 acted on by the ferment. Chemical investigations were made as 

 regards the precipitability of the mucilages — Algin, Fucoidin, also the 

 mucilages of Ceramiam (in G. ruhrum), of Furcellaria (in F. fast iy lata), 

 of Dumontia {D. fit if or mis). The three latter were all precipita,ted by 

 an acid " Leinlosung " (solution of linseed). The mucilages of Ceramiiim 

 and Furcellaria are very closely allied to one another (and probably also 

 to that of "Carrageen," Chondrus); while that of Damontia is the type 

 of another group of Floridean mucilages, which are not precipitated by 

 ammonium sulphate, and do not congeal on cooling. A. Gepp. 



Some Plants from Tropical Sea Gardens. — M. A. How^e {Nat. 

 History, 1920, 20, 560-68, figs.; see also Gontr. New York Bot. Gard., 

 1921, Xo. 226, 560-68). A popular and vivid account of the habit 

 and surroundings of marine alg^e in the subtropics of the Xorth 

 American coasts and adjacent islands. The richest areas visited were 

 Bermuda, Florida Keys, and the coast of California. The masses of 

 Siphonea3 which in many places carpet the sea bottom, the mats of Bryo- 

 thamnion triquetrum., the kelps and other brown algai, are picturesquely 



