47° BOTANICAL GAZETTE [JUNE 
will still be unsatisfactory to cytologists who hope to standardize the essentials 
of nuclear behavior practically throughout the plant realm; and the convic- 
tion will persist that imperfect fixation within the resistant walls of the resting 
body has masked the appearance of mitotic divisions conforming to those of 
the prosorus in this species, of the resting sporangium in S. decipiens and 
S. puerariae, of Rhodochytrium, and others 
This work affords no support to the view advanced by Orton? and KERN 
that the “primordial sphere” in Synchytrium is a chimera composed of a 
parasitic plasmodium enveloping an almost unmodified host nucleus. Figures 
of the type on which this view is based are interpreted as resulting from 
multiple infections, by which a number of zoospores come to lie about a single 
host nucleus. Subsequent divisions of the host cell distribute the super- 
numerary spores, leaving usually only one in each host cell. The reviewer, 
stages of development up to resting sporangia. Furthermore, a series of 
preparations is readily obtained showing that, contrary to the view of ORTON 
d Kern, the primary nucleus of the cyst is the direct outgrowth of the 
zoospore nucleus, the host cell nucleus being crowded off to one side of the 
cyst, where it finally disintegrates. 
Wirson” has published a more detailed account of the work on which his 
preliminary paper™ on Urophlyctis was based, but the conclusions of both are 
identical. The direct functioning of the resting body as a sporangium 
the production of the resting “spores” in lysigenous cavities divelonis in 
the host tissues by a parasitic plasmodium are maintaine 
Scott’ found that the resting spores germinate by the proliferation of 
one to fifteen sporangia through pores of which the zoospores escape. JO : 
and DRECHSLER’s limited observations on germination are in agreement with 
the latter. As for the accounts of cytological details and life cycle of the 
pathogen, it seems evident that Jones and DrecusLER have made their 
wart disease of alfalfa and war is Urophivedts alfalfae, if that name is to 
survive, must remain temporarily suspended, but the fine preparations of 
Jones and DReEcHSLER obtained by dissecting the parasite from infected 
tissues and showing in detail the relations of turbinate cells, hyphae, ie 
spores, and haustoria leave no doubt that the organism which is the type 10 
Urophlyctis is the one they studied. On the other hand, WiItson has aide 
9 Orton, C. R., and Kern, F. D., The sees wart disease. Penn. State College 
Agric. Exp. Sta. Bull, 156. pp. 16. fas 4. 2 
© Witson, O. T., Crown-gall of paca poe Gaz. 70:51-68. pls. 7-10. 1920: 
- , The crown-gall of alfalfa. Science 41:797. 1915. 
Scorr, C. BE. : Povasansaoons note on the germination of Urophiyctis alfalfae. 
Science 52: es 26. 
