June 12, 1903.] 



SCIENCE. 



937 



limits, only one member of the higher and 

 heterocysted Cyanophycege has been noted, 

 viz., Hapalosiphon laminosus. This species 

 does not reach the upper temperature 

 limits, even for the chlorophyllose forms. 

 The majority of the chlorophyllose forms 

 are either species of Phormidium or uni- 

 cellular forms peculiar, as far as known at 

 present, to the thermal waters. The 

 chlorophylless forms, as far as detected, 

 are filamentous, very slender, and belong 

 to the group known as the sulphur bac- 

 teria. All of these forms are very closely 

 related, even the so-called sulphur bacteria 

 being little else than colorless species of 

 Ph07-midium. A matter to be emphasized 

 is this— that all of the strictly thermal 

 organisms are low forms, not even repre- 

 senting the higher differentiation in the 

 group to which they belong. 



The question is always raised, in the 

 ease of the thermal organisms, as to the 

 nature of the protoplasmic contents of the 

 cells. "What is it that enables the proto- 

 plasm of the thermal organisms to with- 

 stand a temperature which coagulates, and 

 consequently kills, the protoplasm of the 

 majority of organisms. We find that 

 when a proteid, like egg albumen, is free 

 from water, it does not coagulate at the 

 very highest temperatures which leave it 

 unburned, and that the less the content of 

 water, the higher the temperature of coagu- 

 lation. The cell structure in the Schizo- 

 phyta is peculiar, being quite different 

 from that of other groups of organisms. 

 While the details are not satisfactorily set- 

 tled, there seems to be a certainty that 

 there is less differentiation than in other 

 groups. Whether we believe that the pro- 

 toplast is all nucleus or whether we believe 

 that it is all cytoplasm, it remains clear 

 that it is different from the protoplast of 

 other groups of organisms and affords us 

 room for surmise. There is nothing, so 



far as my own study of the Cyanophyceffi 

 cell is concerned, to indicate that the 

 protoplasm contains so little water as to 

 render it incoagulable by the higher tem- 

 peratures which it end^^res. It seems 

 rather that there may be some important 

 difference in the essential proteids of the 

 mixture, or in the nature of the constitu- 

 tion of the substance, if it be regarded as 

 simple, which renders it less coagulable, a 

 difference similar to that existing between 

 a substance of the groiip of the vitellins 

 and one of the group of the globulins. 

 William Albert Setchell. 



SGIElflTIFW BOOKS. 



THE SUGAR INDUSTRY. 



Anleitung zur Untersuchung der fiir die 

 Zuckerindustrie in Betracht kommenden 

 Bohmaterialien, Produhte, NehenproduMe 

 und Hilfssuhstanzen. Sechste umgearbei- 

 tete und vermehrte Auflage. Von E. 

 FRiJHLiNG. Braunschweig, Friedrich Vie- 

 weg und Sohn. 1903. Pp. xxi + 505. 

 Marks 12.00. 



The rapid advances made in sugar chem- 

 istry within the past few years have necessi- 

 tated a thorough revision of and the intro- 

 duction of a considerable amount of new mat- 

 ter in this, the sixth, edition of Friihling's 

 ' Anleitung.' 



Examination of the book shows that the 

 author has spared no pains to do justice to 

 his self-imposed task. 



Adoption of the regulations of the Inter- 

 national Commission for Uniform Methods 

 of Sugar Analysis, Paris, July 24, 1900, has 

 of course resulted in the introduction of 

 fundamental changes. The metric cubic cen- 

 timeter has replaced the Mohr cubic centi- 

 meter; the normal sugar weight is now 26,000 

 grams instead of 26,048 grams; 20° Centi- 

 grade has been accepted as the standard tem- 

 perature for the preparation and the polariza- 

 tion of sugar solutions. Space is given to 

 the extensive table showing the relation be- 

 tween the specific gravity of sucrose solutions 

 at 20° 0. and the sucrose percentage of such 



