262 BOTANICAL GAZETTE • [September 



springing from the same point, although one is directed backward and sidewise 

 in such a manner as to give the appearance of the short lateral cilium that has 

 hitherto figured in the descriptions of this and some other genera of biflagellate 

 Archimycetes. They are distinctly diplanetic and show a pulsating vacuole 

 during the interval between the two periods of activity. Soon after infection 

 the young parasites are lost to view in the host protoplasm, but retain their 

 individuality and develop into zoosporangia without fusing to form plasmodia. 

 The parasite becomes coenocytic by nuclear division on the beginning 

 of growth. The nuclei, which show the complete concentration of the chro- 

 matin into the karyosome characteristic of most chytridiaceous nuclei, appear 

 to divide exclusively by mitosis of a type not very dissimilar from that 

 of Synchytrium, but no astral bodies were seen. The chromosomes are approxi- 

 mately six in number. Segmentation is believed to be simultaneous, and begins 

 at least before the sporangium enters the period of rest which it often under- 

 goes before sporulation. The formation of resting spores was found to be 

 dependent on conditions in the culture which are described. The small 

 adjacent cells are definitely shown to be antheridia and the transfer of their 

 coenocytic protoplasm to that of the egg is figured. The number of nuclei of 

 the gametes unfortunately is not stated, but one would judge from the figures 

 that it approximates ioo. The fate of the male pronuclei after entering the 

 egg could not be definitely followed, but it is believed that they fuse in pairs 

 with the female pronuclei. The author concludes that " these forms seem to be 

 primitive sexual organisms of the oomycete type. The influence of external 

 conditions on the development of the sexual stage, the mode of fertilization, the 

 unequal size of the two gametes, and the apparent morphological equivalence 

 of these gametes with the sporangia, seem to the writer to point to that assump- 

 tion." — Robert F. Griggs. 



An epiphytic Tillandsia.— The "ball moss," Tillandsia recurvata, is 

 found growing epiphytically upon many tree species in the vicinity of Austin, 

 Texas, in such abundance as to be detrimental to its host. Birge 17 has found 

 that any damage resulting to the supporting tree must be due to interferenc i 

 with the light supply, as the short holdfast roots merely furnish mechanical 

 support for the moss, the water and salts necessary for the life of the plant being 

 absorbed exclusively by the scale-covered leaves. A sufficient amount may 

 be obtained from three hours dew or rain to last the plant for 38 hours. The 

 leaves are well supplied with chlorophyll in minute oblong plastids, and the 

 complete independence of the plant is shown not only by the entire absence ot 

 any organic connection with the living tissues of the host, but also by the fact 

 that it thrives upon old board fences and even upon electric wire insulators. 

 It seems to thrive best in semi-arid conditions. Shade trees may be freed 

 from the epiphyte by scraping off the larger plants before the dissemination of 



** Birge, Willie I., The anatomy and some biological aspects of the "ball moss, 

 Tillandsia recurvata L. Univ. Texas Bull. 194. pp. 24. pis. 10. 191 1. 



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