234 BOTANICAL GAZETTE [MARCH 
spores are differentiated and set He a 7 partial differentiation and move- 
ment of the spo rt of the first swarming period 
of the zoospores eu ‘the Saprolegniales. This view derives diplanetism from a 
more primitive state among the lower fungi, while there is nothing among the 
algae which corresponds to the phenomenon. 
It is further pointed out that some other phenomenon, such as heterogamy, 
isogamy, and the proliferation of the sporangium, each have a primitive counter- 
part among the Chytridiales, and can be traced in a natural series to the Sapro- 
legniales and Oomycetes. For some of the phenomena, like the proliferation 
of the sporangium, there is no counterpart whatever among the algae.— 
H. HASSELBRING. 
Cultures of Uredineae.—In continuation of the long series of experiments in 
his cultural work on the Uredineae, the cultures made in 1908 have been reported 
ArTHUR.'’ The most interesting result of the work of that year is the dis- 
covery that the aecidial stage of Gymnosporangium externum Arthur and Ker 
(described as new) occurs on a herbaceous perennial, Porteranthus stipulatus 
(Muhl.) Britton. This is the only case known of the occurrence of an aecidium 
of Gymnosporangium on a plant outside of the Pomaceae. Another unusual 
case is that of G. Libocedri (P. Henn.) Kern, whose aecidial stage is shown to be 
Aecidium Blasdaleanum D. and H., a true aecidium and not belonging to the 
Roestelia type as in all other Gymnosporangia. Series of cultures with 13 species 
of rusts gave negative results, and cultures with 23 species confirmed and supple- 
been worked out for the first time: Puccinia absinthii DC. on Artemisia dracuncu- 
loides Pursh has no aecidia, but has pycnidia on the same host; P. macrospora 
(Peck) Arthur on Carex comosa Boott sown on Smilax hispida Muhl.; P. patruclis 
Arth. on Carex pratensis Dreej. sown on Agoseris glauca (Pursh) Green; P. cine- 
rea Arth. on Puccinellia airoides (Nutt.) Wats. and Coult. sown on Oxygraphis 
cymbalaria (Pursh) Prantl; P. Koeleriae Arth. on Koeleria cristata (L-) Pers. 
sown on Mahonia aquijolium (Pursh) Nutt.; P. alternans Arth. on Bromus Por- 
teri (Coult.) Nash sown on Thalictrum dioicum L.; P. obliterata Arth. on Agte 
pyron biflorum R. and S. sown on fetid taeda L.; P. Muhlenber, giae 
Arth. and ate on Muhlenbergia glomerata Trin. sown on Callirhoe molucrata 
(T. and G.) A. Gray; bose hoenstios Libocedri (P. Henn.) Kern on 
cedrus decurrens oe sown on Crataegus Pringlei Sarg.; and 
and Kern on Juniperus virginiana L. sown on Porteranthus st ipulatus 
Britt.—H. HAssELBRING. 
7 
m 
(Muhl.) 
Gymnosporangium.—Another interesting example showing the 
logy of 
eg degree of differentiation existing among some species of parasitic 
1S ARTHUR, J. C., Cultures of Uredineae in 1908. Mycologia 1:225-250- 
1909. : 
