492 SUMMARY OF CURRENT RESEARCHES RELATING TO 



into an amorphous pale brownish mass. They correspond well with the 

 mucilage glands of Yendo. The author describes the effect of certain 

 re-agents on the contents of these cells. The plantlets, arising from 

 cultures which were started on February 8, were damaged by heat 

 towards the end of May, and very few of the half-dead plants showed 

 the fucosau reservoirs. In the living as in the dead tissue, the cell- 

 contents had become transformed into a deep brown, compact, contracted 

 mass, resembling a tannic composition already recorded by the author 

 for several Phteosporea?. These brown cells are doubtless the trans- 

 formed fucosan reservoirs, and seem to indicate that the fucosan in 

 large globules is not utilized by the plant. Whether this transforma- 

 tion is however normal or caused by adverse conditions the author 

 cannot say. 



The reservoirs of fucosan, and later on the cells with brown contents, 

 are situated in the monostromatic portion of the lamina. The basal 

 distromatic portion showed none of them. Wille has recorded for 

 A. esculenta a deep mechanical tissue for the storing of fucosan, but 

 does not mention any element comparable with these mucilage glands. 

 Unless these have been overlooked, they are therefore confined to the 

 young plantlets ; while in Undaria pimiatifida they are only recorded 

 by Yendo on plants with a length exceeding 7 • 5 mm. The author's 

 efforts to examine small plants of AJaria grown under natural conditions 

 at Roscoff were defeated by the condition of the sea, but he is disposed 

 to believe that young sporopliylls of Alar la harbour similar organs, 

 beneath the epidermis. 



The mucilage glands of Undaria are therefore fucosan reservoii-s 

 like those of A. esculenta, and although the possible transformation of 

 fucosan into mucilage may not be proved, notwithstanding the identical 

 action of certain colouring reagents, still the presence of these particular 

 cells in precisely the four species which have no muciferous canals, is 

 distinctly worthy of attention. 



Fungi. 

 (By A. LoERAiN Sjiith, F.L.S.) 



Phytophthora infestans.* — F. D. Kern and C. R. Orton have 

 investigated an attack on tomatoes by this fungus in Pennsylvania. 

 It has already been recorded on tomato plants, but is uncommon and 

 not usually very important economically. On this occasion it caused 

 serious and wide-spread damage. The weather had been unfavourable 

 for the setting of the fruit, and it is suggested that this might have 

 encouraged the growth of the fungus. 



Marine Fungi Imperfecti.f— G. K. Sutherland has investigated a 

 number of these fungi in the course of his work on marine Ascomy- 

 cetes. He describes several Hyphomycetes : Cladosporium algarum, the 



* Phytopathology, vi. (1916) pp. 284-7 (2 figs.), 

 t New Phytologist, xv. (1916) pp. 35-48. 



