SO SUMMARY OF CURRENT RESEARCHES RELATING TO 



from P. Hieracii, and also from P. montevago, a new form that grows 

 only on ffgpochceris uniflora. He established also two forms for 

 P. carduorum. 



Wilhelm Muller* has made an exhaustive study of the Melampsoree 

 on species of Euphorbia. He finds that they can be divided into 

 definite classes according to the form of the teleutospore and the thick- 

 ness of the wall. He divides them thus into five different types. He 

 finds, further, that those with elongate spores and thickened apex belong 

 to southern lands, while those with short thin-walled spores are found 

 in Middle and North Europe. It is possible also that the length of the 

 spores corresponds with the length of the palisade cells. Measurements 

 and drawings of the teleutospores of many of the species are given, and 

 the size of both teleutospores and uredospores are printed in tabular 

 form. 



Morphology of the Rusts.f — A. H. Christman reviews the theories 

 held by successive workers on the origin of the different stages in the life- 

 cycle of the Uredineag, and then proceeds to give his own interpretations 

 which he bases on the examination of certain spore types that do not 

 originate in a fusion-cell. He finds one of these types in the secondary 

 uredospores of Pkragmidium PotentillcB-canadensis. They arise from 

 a large basal cell which contains two nuclei, and is, he considers, 

 equivalent to the basidium or basal cell of the JEcidium and teleutospore 

 stages. Conjugate division of the basal cell-nuclei takes place, and an 

 upper cell is cut off — the first spore initial cell. The division of this 

 cell provides the stalk and the uredospore, the stalk corresponding to 

 the sterile cell in the jEcidiwn. Meanwhile the basal-cell has budded 

 out and formed another uredospore initial cell. The difference between 

 this formation and that of the primary uredosorus is, that in the latter 

 the underlying mycelium is uninucleate, while the mycelium from which 

 the secondary spores arise is binucleate. Christman also examined a 

 teleutospore form, Puccinia Podophylli, and found a similar series of 

 phenomena to that already described. Occasionally trinucleate cells 

 were observed, suggesting possible pathological migrations of nuclei. 



Christman holds with Blackman that the sporophyte stage begins 

 with the associated nuclei in the basal cell, and that there is a series 

 of asexual reproductive cycles within the sporophyte generation. The 

 gametophyte he considers to be the primitive original generation, and 

 the autcecious rusts probably older than the hetercecious. 



New Boletus.} — S. Belli describes at some length Boletus sardous 

 sp. n., which grows throughout Sardinia. The very bulbous stem, large 

 pores, and the colour and form of the spores, differentiate it completely 

 from the two species most nearly allied, B. granulatus and B. badius. 

 It grows most abundantly under Cistus trees. The fungus is reproduced 

 in a coloured plate. 



Recent Work on Fungi. § — I. Gallaud continues his review of the 

 different papers that have been published, especially on the cytology of 



* Centralbl. Bakt., xix. (1907) pp. 544-63 (31 figs.). 



t Bot. Gazette, xliv. (1907) pp. 81-100 (1 pi.). 



% Atti Accad. Sci. Torino, xlii. (1907) pp. 1024-30 (1 col. pi.). 



§ Rev. Gen. Bot., xix. (1907) pp. 459-64 and 506-12 (11 figs.). 



