﻿13- 



REPRODUCTIVE STRUCTURES. 



have the appearance of quite clear chalcedony. It was found possible, however, to 

 increase the differentiation of the main features by carefully boiling the fruit in a 

 strong sugar solution for several days and then immersing for a considerable time 

 in strong sulphuric acid. Some such method of procedure will doubtless be found 

 available in bringing hidden structural details to light in yet other cases where 

 structure is present but not differentiated by traces of carbon along the cell walls 

 or by natural iron staining. Artificial staining methods used for agates are 



suggested. 



T.50S. S3 S3. 



Fig. 66.— Cycadeoidea dacotensis(». S. 353. T. 505. X'2'i. Longitudinal section through ovulate 

 cone. This cone belongs to the same series as those shown in figure 29, having been removed before the 

 remainder of the trunk was polished. The summit was even with the surface of the armor. (Cf. photo- 

 graph of this section, Plate XXXII, also of the cone, Plate XLI1I, No. 5.) 



The fruit before us is of flattened elliptical outline and beautifully symmetrical. 

 It is 55 mm. in length, with a major diameter of 35 mm. and a minor diameter of 

 25 mm. (The figure shows the fruit as cut longitudinally on the short diameter 

 in radial longitudinal direction to the trunk.) Bracts and bract hairs envelop most 

 of the surface, but in places the characteristic surface sculpturing formed by the tips 

 of the micropylar tubes and the surrounding interseminal scales is distinct. Below 

 the seed zone and above the insertion of the bracts a belt of the receptacular portion 

 about 1 cm. broad is prettily fluted to meet the appressed enveloping bracts. The 

 young and small seeds are far more numerous than in cones of the preceding species. 

 The seed stems do not vary greatly in length, as the receptacle is not simply convex 

 or globular but of elongate inverted top-shape, relatively flattened to the same 

 degree as the entire fruit. The cone is evidently half-grown or larger, although the 

 earlier presence or absence of a staminate disk is not readily determinable. 



