148 THE AMERICAN MIDLAND NATURALIST 



the central insertion point, 15 mm. apart on the nodal line, alternating 

 on the neighboring nodes, with 12-16 ribs converging on each side to 

 them. Lea} scars, if any, indistinct. 



The type specimen, consisting of a cast of the medullary 

 cavity, has been subjected to flattening influences, resulting in a 

 splitting of the stem length-wise. It is composed of 3 nodes in a 

 fair state of preservation, the upper two 28 mm. in length while the 

 lower is 23 mm., their circumferences being 13, 12 1-2, and 12 cm. 

 respectively. A portion of it is covered with a thick and somewhat 

 coalv bark of about 4 mm. thickness at some places, and upon which 

 the furrows appear but indistinctly. The combined thickness of 

 the bark and medullary cavity is from 80-83 mm - at tne upper (?) 

 end, while the lower (?) end has a diameter of 41 mm. 



Following the nomenclature as proposed by Jongmaus', 

 this specimen evidently is a member of the cruciatus group. With 

 7 branch scars it would tend to approximate the Calamites cruciatus 

 septenarius of Sterzel. The following distinguishing features 

 appear. Of the two more clearly distinguished varieties of this 

 latter form, the variety fascialus of Sterzel is excluded by the 

 shortness of its joints, the presence of leaf traces, and the minimum 

 number of ribs converging to form the branch scars. 



The rather incompletely described variety Brongniarti of 

 Sternburg is eliminated through the possession of leaf scars, absence 

 of swellings at the nodes, and the want of distinct impressions of 

 the ribs. 



In short, the number of estimated branch scars, the number of 

 ribs converging to meet these, their width and distance from one 

 another, considered with the length, diameter and circumference 

 of the joints widely separate this form from any hitherto described 

 as belonging to this group, making it clear that we are dealing with 

 a new species which I have dedicated to Prof. R. G. Harrison of 

 Vale University, an inspiring worker in taxonomic fields. 



Calamites multifoliatus n. sp. 

 PI. II., figs. 1. 2 



Internodes 36-38 cm. in length, broader than long. Articulations 

 somewhat constricted, increasing in size from the base (?) oj the stem. 

 Ribs at least 4 times the width of the furrows, well defined, half-round, 

 pointed at the ends, terminating in leaf scars at the nodes, or converging 

 in group oj 2-4 to the nodal line. Apparently two branch scars to the 





