Cytologie und Befruchtung. 261 



This sexual fusion of gametes in the aecidium shows that 

 'Dangeard and S api n-Tr ou f f y were wrong in regarding 

 the teleutospore as an es^g. On the other hand, the resiiits 

 Support the view of Arthur, that the aecidium represents the 

 stage of sexual rejuvenescence. 



Charles J. Chamberlain (Chicago). 



•COKER, W. C, On the spores ofcertain Coniferae. (Bo- 

 tanical Gazette. XXXVlll. September 1904. p. 206—213. 

 fs. 24.) 



The author investigates the divisions taking place in the 

 microspores and in the formation of the megaspores in several 

 genera and a number of species of Conifers. In Ciipressiis 

 goveniana, C. macrocarpa, C. benthamiana, Taxus baccata and 

 varieties epacroides, fastigiata, ciispidata, and adpressa, Jiini- 

 periis spliaerica, J. Cliineusis there are no divisions in the 

 microspore previous to anthesis. In Chamaecyparis lawsoniana, 

 C. sphaerica, C. chlnensis, C. obtiisa, C. pisifera, Callitris sp. 

 Ciyptomeria japonica and var., Thuja orientalis there is a 

 Single division before anthesis. The author finds typicai tetrad 

 division in the megaspore mother cells of Thuja and Taxus. 



E. C. Jeffrey. 



Faraier, J. B. and J. E. S. MoORE, On the Maiotic Phase 

 (Reduction Division) in Animals and Plauts. (The 

 Quarterly Journal of Microscopical Science. Vol. XLVTII. 

 1905. p. 489—557. PI. 34—41.) 



Farmer, J. B. and Dorothy Shore, On the Structure and 

 Development of the Somatic and Heterotype 

 Chrom osomes of Tradescantia Virginica. (Ibid. Vol. 

 XLVIII. 1905. p. 559—569. PI. 42, 43.) , 



In the first paper the authors give in füll the results which 

 were published very briefly in Proc. Royal Soc. May 1903 

 (B. C. XCV. p. 34.) 



The authors use the term maiosis or maiotic phase 

 (f-isUriGii:, reduction; /neioniyjK, that which is reduced) for the 

 whole series of nuclear changes included in the two divisions 

 designated heterotype and homotype by Flemming. Maiosis 

 is thus a very definite phase in the cellular life-cycle of nearly 

 all metazoa and metaphyta; and the füll life-cycle in these forms 

 can be very conveniently devided into three phases, pre- 

 maiotic, maiotic and post-m ai otic; the first phase being 

 intercalated between fertilization and maiosis and being present 

 in animals and plants, the last phase being intercalated be- 

 tween maiosis and fertilization and being regularly present in 

 plants though normally absent in animals. The term homo- 

 type is restricted to its original meaning as applying only to 

 the second maiotic division and is not extended to the somatic 

 divisions generally. 



