G. R. Wielancl — Cycadeoidean Flower-hud Structure. 121 



collected some two years earlier at the same locality. My own 

 search for new material was, of course, carried out with far 

 more care than that of the earlier collectors, who quite without 

 exception had mainly sought huge or otherwise striking speci- 

 mens. 



Specific position of specimens. 



For trunk and floral characters of the type before me, we 

 may then use both the earlier trunk fragment and the isolated 

 specimen in full confidence that both are of precisely the same 

 species. Furthermore, both may be provisionally referred to 

 the same species as the great type Cycadeoidea colossalis of 

 the U. S. National Museum. In the original descriptions of 

 this specimen no very clear distinction from the prototype 

 of the Minnekahta series of species, Cycadeoidea dacotensis, is 

 definitely pointed out. But a close reading of the measure- 

 ments shows that the leaf bases are very small, and the floral 

 axes of only medium size. In C dacotensis the lateral and 

 vertical diagonals through the leaf bases measure from 16 to 

 26 mm and 10 to 16 mm respectively as compared with 13 to 16 mm 

 and 8 to 12 mm in the C. colossalis. This is a really great and 

 striking difference, when it is recalled that the largest of the 

 trunks or branches definitely proven to belong to Cycadeoidea 

 dacotensis weighs a scant hundred kilograms, whereas the 

 great National Museum type exceeds 300 kilograms in weight, 

 being one of the largest single stems, if not " the largest," in 

 the world. The huge columnar trunk of the Yale Collection 

 C. inyens, which yielded the first flower buds with disk 

 features studied, has the greatest recorded weight, 303 f 91 kg.,* 

 and after it comes the famous Dresden trunk Cycadeoidea 

 Reichenbachiana. The largest known single branch is the 

 superb specimen shown in Plate Y, fig. 1, of my American 

 Fossil Cycads with a weight of 147 kg., and the greatest 

 weight yet determined in a branching aggregate is 841 pounds, 

 (382 kgs.) seen in the group figured in Plates XII and XIII 

 of the American Fossil Cycads. 



No further facts need be given to show that the type of 

 C. colossalis has distinctive features, even in the absence of the 

 closer knowledge of its actual woody cylinder and other of the 

 more searching details of trunk structure so much to be desired. 

 Nor do I now need to go on seriatim with other forms related 

 to C. colossalis and show how they differ in first one, then 

 another of the known features. 



* In the late Fall of the year 1898 I re-examined the exact spot where 

 C. ingens was collected (cf. American Fossil Cycads, Plate XLIX, upper 

 figure), finding a few additional fragments from the apex of the trunk 

 increasing the weight of this great type to over 304 kilograms. 



