giospermous 



1907] CURRENT LITERATURE 319 



a collecting and incubating apparatus for the microspores." The ''carpellarj 

 leaf" was shed at maturity and resembles a winged seed. — J. M. C. 



The flowering plants of the Mesozoic. — In a recent address Scott^^ has 

 brought together the recent discoveries among the Cycadophytes, especially those 

 of WiELAND among the Bennettitales, and has seen in the structure of their strobili 

 strong suggestions of angiospermous flowers. Such a connection would su<};gest 

 the possibility that the angiosperms may have been derived from the Filicineae 

 by a *'short cut;" that the evolution of the angiospermous flower was a process of 

 reduction; and that the presumption that the simplest ai 

 are the most primitive is no longer tenable. — J. ^M. C. 



The Taxoideae. — Miss Robertson^^ has brought together the results of the 

 recent researches among the Taxineae, with the view of reaching some conclusion 

 as to the vexed question of phylogeny. She reaches the conclusion that the group 

 has retained many relatively primitive characters, but has become considerably 

 specialized; that it may be regarded as an oflfshoot from the Cordaitales, which 

 in turn are derived from the Cycadoiilices. The author also suggests that the 

 *^ female flower" of Taxus "more closely recalls that of Cordaites than that of 

 any other known plant." — J. M. C, 



Embryology of Rhizophora. — CooK^^ has succeeded in securing some material 

 for the study of the emhiyology of R, Mangle. Only one of the four ovules reaches 

 the seed stage; the hypodermal archesporium cuts off two tapetal cells; the linear 

 tetrad is probably formed; endosperm formation is abundant; the embryogeny 

 is probably of the Capsella-type ; during the first growth of the cotyledons about 



»erra 



the sac and lie in the ovary cavity. — -J. M. C. 



Endemic species and mutation.— WiLLis/4 in foflowing up the suggestions 

 of his work upon the flora of Mt. Ritigala/^ has constructed an argument against 

 the origin of species by natural selection and in favor of origin by mutation. He 

 maintains that the evidence of the endemic species on Mt. Ritigala, of Ceylon in 

 general, of Mauritius, and of New Zealand completely proves his position. 

 J. M. C. 



21 



Scott, D. H., The follo^-ing plants of the Mesozoic age, in the light of recent 



discoveries 



6-9 



"Robertson, Agnes, The Taxoideae: A phylogenetic study. New Phytol. 

 6:92-102. pi. I. 1907. 



a3 CooK, Melville Thurston, The embryolog}^ of Rhhophora Mangk. Bull. 

 Torr. Bot. Club 34:271-277. pis. 22, 23. 1907. 



34 Willis, J. C, Some e\'idence against the theory of the origin of species by 

 natural selection of infinitesimal variations, and in favor of origin by mutation. Annals 

 Roy. Bot. Gard. Peradeniya 4:1-15. 1907- 



»5 BoT. Gazette 43:353. 1907. 



