NATURE 



553 



THURSDAY, APRIL ii, il 



BRITISH UREDINEyE AND USTILAGINEAL. 

 A Monograph of the British Uredinea ani Ustilaginecc. 

 With an Account of their Biology, including the 

 Methods of observing the Germination of their Spores 

 and of their Experimental Culture. By Charles B. 

 Plowright, F.L.S., M.R.C.S. Illustrated with Wood- 

 cuts and Eight Plates. (London : Kegan Paul, Trench, 

 and Co., 1889.) 



MR. PLOWRIGHT'S monograph will at once take 

 its rank as the chief English authority on the 

 interesting groups of parasitic Fungi to which it relates. 

 The results of the author's important original investiga- 

 tions are here incorporated with those of other observers 

 to form a work which brings our knowledge of these 

 plants thoroughly up to date. The greater part of the 

 book is systematic, the detailed description of species 

 being preceded by a general account of the structure and 

 life-history of the two orders. These introductory 

 chapters will probably appeal most to the reader who 

 is not a specialist in mycology, though the biological 

 notes attached to the specific descriptions are also of 

 great interest, and effectually relieve the dryness which is 

 usually inseparable from purely taxonomic work. 



In the first chapter a short summary of the biology of 

 the Uredineae is given. This is, perhaps, if anything, 

 rather too short, but of course some previous knowledge 

 in the reader is assumed. The Uredineae, which are 

 now probably the best known family of pleomorphic 

 Fungi, are arranged by the author, in agreement with 

 Schroter and Winter, in biological groups, according to 

 the varying combinations in which their different forms 

 of reproductive organs are present. These groups are 

 made use of for the division of the larger genera into 

 sub-genera. The system adopted may be illustrated by 

 the classification of the species in the largest genus, 

 Puccinia, in which all the modifications are represented. 

 The sub-genera are six in number. First we have 

 Eupuccinia, characterized by the presence of all the 

 four reproductive structures : spermogonia, aecidiospores, 

 uredospores, and teleutospores. This sub-genus is again 

 divided into Anteupuccinia, which is autoecious, all the 

 forms occurring on the same host-plant, and Hetero- 

 puccinia, in which hetercecism prevails, the spermogonia 

 and aecidiospores being developed on one host, and the 

 uredospores and teleutospores on another plant belonging 

 to a distinct genus. The other sub-genera of Puccinia are 

 all autoecious. In Brachypuccinia the aecidiospores are 

 absent, while in Hemipuccinia the spermogonia also 

 disappear, only uredospores and teleutospores being 

 developed. In Pucciniopsis only aecidiospores and 

 teleutospores are usually present, while in both the 

 remaining sub-genera, Micropuccinia and Leptopuccinia, 

 the teleutospores alone occur, the two groups differing 

 from one another in the fact that the teleutospores of 

 Micropuccinia are of the usual type, requiring a period 

 of rest before germination, while those of Leptopuccinia 

 germinate on the host-plant as soon as they are ripe. 

 The essential character of the teleutospores is the pro- 

 duction of a small promycelium which immediately bears 

 Vol. XXXIX.— No. 1015. 



promycelial spores (sporidia), the latter being the bodies 

 which directly infect the host. Thus the spores of 

 Endophyllum are classed as teleutospores, on account 

 of their method of germination, though in all other 

 respects they agree with the aecidiospores of other 

 genera. The author regards the teleutospores as the 

 constant characteristic of the Uredineae, believing that 

 their apparent absence in many forms is due to our 

 imperfect knowledge of their life-history. 



The second chapter is devoted to the mycelium of the 

 Uredineae. Here the description of the cell-contents 

 strikes us as rather inadequate, but the subject is 

 a difficult one to investigate. The often remarkable 

 influence of the localized mycelium on the tissue of the 

 host is well described. 



In the next chapter those puzzling organs, the spermo- 

 gonia, are described, and their functions discussed. The 

 author and others have observed that in sugar- solution 

 the spermatia pullulate, like yeast-cells. It was not, 

 however, found possible to infect the host-plant with 

 them. Still the author inclines to the view that the 

 so-called spermatia are conidia rather than fertilizing 

 bodies, a view which the observations of Moller on the 

 spermatia of Lichens certainly render probable. If Mr. 

 Massee's isolated observation of an antheridium in the 

 -(Ecidium form of Uromyces Pace should be confirmed, 

 we shall have to seek the male organs of the Uredineae 

 elsewhere than in their spermogonia. 



In the chapter on the aecidiospores there is a want of 

 clearness in describing their development. The account 

 given recalls the now exploded Schleidenian theory of 

 " free cell-formation," whereas the aecidiospores are in 

 fact formed by ordinary cell-division. 



The uredospores and teleutospores are described in 

 the two following chapters, which call for no special 

 remark. Most of the facts brought forward will be 

 familiar to those who know de Bary's work on the Fungi. 



Chapter VII. deals with the interesting phenomenon 

 of hetercecism, and the curious history of its discovery 

 in the case of the mildew of wheat is well told. The old 

 observations, dating back to the middle of the last century, 

 on the influence of the barberry in producing this disease 

 in corn, are described, and in an appendix the text of the 

 "Barberry Law of Massachusetts" (published in 1755) is 

 given. This law enacted that, " Whereas it has been 

 found by experience that the Blasting of Wheat and other 

 English Grain is often occasioned by Barberry Bushes," 

 these bushes should be extirpated throughout the pro- 

 vince. The true explanation of this mysterious power 

 for evil of the barberry was first given by Sir Joseph 

 Banks in 1805, and shortly afterwards a Danish school- 

 master, Schoeler, made the first successful experiments in 

 infecting wheat with the barberry fungus. Naturally 

 the purely systematic botanists held out for a long time 

 against the popular belief; and it was not until 1865 that 

 the connection between the ./Ecidium of the barberry and 

 the Uredo and Puccinia of the wheat was finally established 

 by de Bary, who thus at last brought the views of scientific 

 men into harmony with those which had long been held 

 by practical farmers. Forty-seven heteroecious species of 

 Uredineae are now known, and the life-history of eleven 

 of these was first worked out by the author. 



The remaining chapters of the introduction deal with 



