ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 2L3 



and the lack of all branching of the thallus. Taken singly, none 

 of these variations from existing types of Halimeda would separate 

 H. Fuggeri from that outwardly variable genus, but taken together 

 they constitute in the author's opinion a sufficient reason for placing 

 H. Fuggeri in a new genus Halimedides. 



JUgagropila Sauteri.* — C. "Wesenberg has made a special study of 

 this alga as it appears in the Lake of Soro in Denmark, where the form 

 of the balls is absolutely regular and the size that of a fist or a child's 

 head. The author reviews shortly some of the literature on the subject, 

 and declares himself almost entirely in accord with F. Brand. A de- 

 scription is given of Lake Soro, with details concerning the geological 

 composition of its beds, the temperature of the water, the plankton, etc. 

 Then follows an account of the different forms of the thallus of ~E. 

 Sauteri, which appear in the lake : (1) individual separate plants ; 

 (2) adherent thallus ; (3) globulous thajlus, (a) balls resting on the 

 bottom of the lake, (b) floating balls ; (4) felty masses. The author 

 then deals with the origin and mutual dependence of the different 

 forms of thallus of jE. Sauteri, treating each form separately. He 

 discusses the question of the rising and falling of the floating balls, 

 and the possibility of a connection between this phenomenon and the 

 presence of a rich plankton and much detritus. He believes, with 

 Brand, that much light is prejudicial to JE. Sauteri. The formation 

 of the balls is, in his opinion, caused by the incessant destruction of the 

 terminal filaments which are directed outwards, this destruction causing 

 the formation of new adventitious filaments. The beating of the 

 waves and the friction against the bottom cause the globular shape, 

 which becomes more pronounced in proportion to the hardness of the 

 earth. 



Fucus serratus in America.f — C. B. Robinson has studied the 

 distribution of this species in America, and finds that it grows plenti- 

 fully in the district lying between Pugwash in Nova Scotia and Eastern 

 Harbour on the west side of Cape Breton. It also occurs at the 

 extreme south-east of Prince Edward Island, in the neighbourhood of 

 Murray Harbour and Cape Bear. On the coast of Pictou Island it is 

 nowhere wanting. 



Sphacelaria cirrosa.J — C. Sauvageau gives a resume of part of his 

 long paper on the different genera of Sphacelariaceas, which is appearing 

 in the Journal de Botanique. This resume deals with Sphacelaria 

 cirrosa, and the species which have from time to time been regarded as 

 synonyms and forms of it. S. Hystrix is regarded by the author as 

 quite distinct from the cirrosa group, and the life-history of this para- 

 site of Cystoseira ericoides is described. The early stages of the plant 

 bear well-developed sexual organs in plurilocular sporangia, and these 

 disappear in May to make room for long and numerous filaments which 

 bear the propagula. It is in this latter stage that the plant has been 

 mistaken for S. cirrosa. During the winter no trace of it is to be 

 found, and in what form it passes through this period of rest is not yet 



* Overs, k. dansk. Vidensk. Selsk. Forh. ii. (1903) pp. I6S-203. 



t Torreva, iii. (19(18) pp. J 32-4. 



% Mem.'Soc. Sci. Phys. et Nat. Bordeaux, iii. (1905) 11 pp. 



