PALEONTOLOGY — CASE, WIELAND. 229 



European museums for comparison. The manuscript of the first monograph 

 has been sent to the Carnegie Institution of Washington, and the second will 

 be forwarded by December first of this year. 



1 



Wieland, G. R., Yale University, New Haven, Connecticut. Grants Nos. 

 628 and 648. Continuation of investigations on fossil cycads. (For pre- 

 vious reports see Year Books Nos. 2-4 and 6-8.) $2,000 



The two memoirs on American fossil cycads announced in previous reports 

 are now nearing completion. Moreover, there is in projection a further gen- 

 eral treatise on the fossil cycadales which should form a notable contribu- 

 tion to our knowledge of the structure and distribution of Mesozoic plants, 

 inasmuch as it now becomes possible to examine in new light the only two 

 well-marked Williamsonia floras hitherto known, namely, those of the York- 

 shire coast and the Gondwanas of India, both of which it is intended to re- 

 study in field and laboratory. 



As indicated last year, the field-work in Mexico, noted as desirable in an 

 earlier report, resulted in the discovery of a profusion of early Mesozoic 

 cycads, including the first series of Williamsonia fruits to be reported from 

 North America. In addition to their definite stratigraphic interest, these 

 Williamsonias of southern Mexico present a noteworthy variety of form and 

 include the most reduced staminate disk yet discovered. As discussed tenta- 

 tively in the Botanical Gazette for last December, the existence of such a 

 flower does suggest polyphyletic origins amongst the angiosperms, and ren- 

 ders more plausible the ascription of certain foliar types found low down in 

 the Cretaceous to such modern and supposedly advanced genera as Viburnum 

 and Nerimn. Indeed, this new evidence, taken in conjunction with the recent 

 discovery of Nathorst that the Rhatic cycad Wielandiella had monantherous 

 microsporophylls as minute as stamens, goes far toward a demonstration of 

 the validity of our theory of angiosperm origin by reduction. 



These complementary studies of Williamsonia floras having been brought 

 thus far forward, active work on the silicified cycads has been resumed, and 

 is now so far advanced that the companion volume to American Fossil Cycads 

 (structure), or that in taxonomy, should be ready to submit for publication 

 during this coming year. As already announced, the results will have more 

 than a merely taxonomic interest, the floral structure of some little-known 

 species having been found to exhibit more variety than was at first anticipated. 



Many additional thin sections of the largest size have been cut. A notable 

 one traverses the lateral armor of a trunk tangentially so as to bring to view 

 no less than 17 strobili in two series about equal in number, the one large 

 with seeds containing proembryos, and a much smaller ovulate series. This 

 latter, in case it should prove young, would show my suggestion that the 

 fossil cycads were more or less monocarpic to require modification. How- 

 ever, the corresponding series of parallel longitudinal sections has been made 

 and it is expected that by comparative study of supplementary series from 



