G. R. Wieland — American Fossil Cycads. 387 



Lignier gives a section of a seed stem from near a seed base 

 (peduncle, figure 27, Plate II), 12 in which the tracheidal cord is 

 followed by fundamental tissue, and this by a layer of cells 

 {assize color ee\ which is in turn surrounded by a single row of 

 cells laterally dovetailing. This alteration at the seed bases 

 has not been observed as yet by the writer, and no doubt must 

 stand as one of the specific variations between the foregoing 

 species. 



Inter seminal Scales. — Five or six of these commonly sur- 

 round each seed stem, and rise beyond the seeds, their tips 

 expanding to form the rounded summit of the fruit. Figure 

 13, Plate X, displays a transverse section of one of these 

 organs cut near its middle height. In the case of cycad 

 JSTo. 77, figure 14, Plate X, the parenchyma surrounding 

 the central vascular strand is not preserved ; but the central 

 strand, the large subepidermal cells (much less continu- 

 ous in this species than in C. Jforierie), and the epidermis, are 

 so uniformly present as to differentiate these tissues as abso- 

 lutely as any staining. From the base toward the summit, as 

 the seed stems decrease in diameter, the scales increase in size 

 by the enlargement of the cross area of the parenchyma cells, 

 which are usually rounded in section and quite elongate. Be- 

 yond the seeds, the cells composing the expanded summits are 

 entirely lignified. In the seed zone, the scales are also more or less 

 lignified and often very thin and flat as they pass between the 

 seeds, where it is sometimes difficult to differentiate them from 

 the seed coats. Exterior to the outer seed stems there is a 

 flattened overlapping series of scales, forming a kind of lateral 

 wall of the fruit several scales in depth. The distal portions 

 of these modified scales are elongate, tetrangular, and lignified, 

 as they appear on the fruit surface. 



It is difficult to detect the several elements of the scales in 

 longitudinal section. That some of the xylem cells are spir- 

 ally marked is certain, and that there is an occasional scalari- 

 form marking is also certain. The woody elements of these 

 scales regularly take their origin below that of the cells of the 

 xylem zone of the seed stems, and in figure 5, Plate VIII, are 

 seen extending down into the parenchymatous cushion as small 

 projecting brushlike groups. 



It need scarcely be pointed out that there is an analogy be- 

 tween these scales and the central bundle of the seed stems, the 

 variation being in a uniformly large central strand, the addition 

 of a broken subepidermal layer with apical sclerotization, and 

 the presence of occasional ducts in the case of the scales. 



The Seeds. — The seeds thus far observed in the present and 

 other species show much variety of preservation. Their study 

 is therefore a difficult one, requiring time, especially for the 



Am. Jour. Sci.— Fourth Series, Yol. YII, No. 41.— May, 1899. 

 26 



