172 



SCIENCE 



[N. S. Vol. XLI. No. 1048 



EndotMa parasitica (American and Chinese 

 strains), E. radicalis and E. radicalis mississippien- 

 sis were grown on a culture medium to which had 

 been added different percentages of commercial 

 tannin and special extracts prepared by Mr. 

 George A. Kerr. Extract "1-X" was soluble in 

 water; "2-X" in water and alcohol; both were 

 tannins, and the second between 95 and 100 per 

 cent. pure. A third extract, "3-X, " contained the 

 coloring matter which is usually estimated as 

 tannin. The results of the experiments indicate 

 (1) that commercial tannins are variable and 

 probably not pure tannin; (2) that ordinary com- 

 mercial tannin and pure tannin extracts are not the 

 same; (3) that we do not know the form or quantity 

 of tannin or tannin-like substances with which the 

 fungus comes in contact in the host plant; (4) 

 that the food supply influences the vigor of the 

 fungus and its power of resistance; (5) that 

 high percentages of tannin usually cause a re- 

 tardation of germination, frequently followed by 

 an abnormal growth of aerial mycelium; (6) E. 

 radicalis mississippiensis was most resistant, E. 

 parasitica second and E. radicalis third; (7) that 

 the American strain of E. parasitica was more 

 resistant than the Chinese strain ; ( 8 ) E. para- 

 sitica may feed to some extent on the tannin; (9) 

 specially prepared pure tannin extracts were less 

 toxic than commercial tannin; (10) coloring ma- 

 terials which are usually estimated as tannins were 

 toxic; (11) tannic acid is toxic to many para- 

 sitic fungi, but there are other compounds as- 

 sociated with it which are more toxic and which 

 may be more important in the economy of the 

 host plant. 



A New North American Endophyllum: J. C. 



Arthub and F. D. Feomme. 



The supposed aeeiospores of Aecidium tubercu- 

 latum Ellis & Kellerm. were found to produce 

 promyeelia and basidiospores when germinated on 

 the surface of water or of a non-nutrient agar or 

 gelatine. They are, therefore, to be considered 

 teliospores of the same character as those present 

 in the genera Endophyllum, and Gymnoconia. The 

 morphological features of this species, especially 

 the cupulate, bullate sorus and the presence of a 

 peridium, together with the habit of perennating 

 in the host are characteristic of the genus Endo- 

 phyllum. 



The fungus occurs on species of CalUrhoe, Sidal- 

 cea and Althaea in Kansas, Nebraska, Colorado 

 and Wyoming. 



This is the first North American rust whose as- 



signment to the genus Endophyllum has been 

 proved by germination tests. 



Sow to Use Aecium, and Similar Terms: J. C. 



Arthue. 



The terms pycnium, aecium, uredinium and 

 telium and their derivatives were introduced into 

 the terminology of mycology by the writer in 1905. 

 These terms were intended to meet certain defi- 

 nite requirements, and not as simplified forms of 

 terms in common use. They have been accepted 

 by maBy writers, either wholly or in part, and 

 have been accorded a place in recent large dic- 

 tionaries. The present paper is intended to point 

 out the application of the terms, and to show 

 wherein some extension of the terms has developed 

 which impairs their value and is likely to lead to 

 confusion of ideas. 



Cultures of TJredineae in 1912, 1913 and 19H: J. 



C. Arthur. 



The present report continues a series extending 

 over sixteen consecutive years on the results ob- 

 tained from protected cultures of various species 

 of rusts. Out of the very large number of trials 

 made during the three years covered by the report, 

 about seventy were successful in producing infec- 

 tion, involving about thirty species. Probably 

 half the successful cultures do little more than, 

 confirm previous work with the same species. A 

 large part of the remainder, however, extend our 

 knowledge of the species considerably. Some show 

 that what have been considered valid species, e. g., 

 Tuocinia tosta, P. vulpincidea and P. Dulichii, are 

 to be reduced to synonymy. A few cultures dem- 

 onstrated the full life history of species never be- 

 fore cultured. 

 The North American Species of Allodus: C. E. 



Orton. 



The genus Allodus of the Uredinales was 

 founded by Arthur in 190& and embraces those 

 species of the genus Puccinia auct. which have 

 only pycnia, aecia (aecidium type) and telia in 

 their life cycle. The present study has been made 

 almost entirely from the taxonomic standpoint and 

 shows in North America about forty-eight species, 



Diagnostic descriptions and a key to the species 

 are included, together with discussions and notes 

 of interest to investigators in this class of fungi. 



Foreign species have been carefully compared, 

 but are not included in the present paper. 



Correlated species of rusts in the genera 

 Dicaeoma, Dasyspora and Uromycopsis have been 

 enumerated so far as time has permitted, and show 

 some interesting genetic relationships. 



