586 SUMMARY OF CURRENT RESEARCHES RELATING TO 



of Asia and Kussia and the Sahara desert in Africa form a natural and 

 efficient barrier between the warm countries and the forests of Europe. 

 The writer has followed Lister's Monograph of the Mycetozoa in his 

 classification. There is one new species recorded, Didymium excelsum, 

 determined by Lister. 



Plasmodiophora Brassicse.* — Feinberg has studied the origin of 

 " finger and toe," the diseased outgrowths on the roots of members of 

 the genus Brassica, in order to throw light on the cause of tumours in 

 the animal kingdom. In sections cut from a diseased cabbage-root he 

 found cells full of masses of spores, others with the amcebaa, and in some 

 cases the plasmodium developing into spores. The spores were small 

 round bodies, rather larger than the nucleoli of the host-cell. They 

 were surrounded by a doable membrane. The amoebae presented a fine 

 protoplasm, with a more or less characteristic nucleus, which was formed 

 of a nucleolus surrounded by a sharp clear zone resembling, according 

 to v. Leyden, the eye of a bird. Feinberg found these nuclei also in 

 malaria parasites, and considers them characteristic of one-celled animal 

 organisms. He did not find the parasites nor the spores in tumours from 

 the human body. 



Streptothrix farcinica.t — Carl Feistmantel has communicated the 

 results of his observations after a long series of experiments on the 

 staining properties of various species of the lower fungi. He discusses 

 the causes that enable stained specimens to resist discoloration by acids 

 and alcohol, and the systematic value of this property. He finds that 

 S. farcinica occupies a position midway between the Actinomycetes 

 (the Streptotrichaceas) and the fungi that resist decoloration by acids. 

 He would, however, use the term Streptothrix for the whole group. - 



Urophlyctis. — In a recently published paper, P. Magnus gave a 

 sketch of the genus and species of Urophlyctis. He describes in the 

 present paper | a disease causing galls on the roots of lucerne, ascribed 

 by Lagerheim to Cladochytrium Alfalfse, but which Magnus considers 

 to belong also to the genus Urophlyctis. The galls occur as small ex- 

 crescences on the main roots of Medicago saliva. The interior is divided 

 into irregular chambers, which are filled with the resting-spores of the 

 fungus. The disease occurs only in damp soil, and is fatal to lucerne 

 plants. It was first described by Lagerheim from Ecuador. It has also 

 been found frequently in Alsace, into which country it has been 

 imported from the former region. 



Fr. Bubak § has discovered in Bohemia Urophlyctis bohemica, a new 

 fungus on plants of Trifolium montanum. The plants attacked fail to 

 flower, and the leaves and petioles become covered with yellow spots and 

 warts caused by the parasite. On the petioles the warts are math 

 larger than on the lamina of the leaf, attaining a diameter of 1 mm. 

 The resting spores are found in the abnormally large parenchyma cells, 

 the walls of which disappear as the fungus ripens. As many as 200 

 re.sting-spores may be contained in each wart. They are convex- 



* Deutsche Med. Wochenschr., No. 3 (1902). 

 t Centralbl. Bakt., l ,e Abt., xxxi. (1902) pp. 433-44. 

 % Ber. Deutscli. Bot. Ges., xx. (1902) pp. 291-6 (1 pi.). 

 § Centralbl. Bakt., 2 te Abt., viii. (1902) pp. 817-21 



