228 FLORA OF LOWER COAL MEASURES OP MISSOURL 



is closed at the base to form an ellipse, tliougli it slightly affects that appear- 

 ance in the pits figured in PI. LXVI, Fig. 4. It may j)roceed on either side 

 from the lateral wings of the leaf scar at the base of the boss. There is 

 nothing on the specimens before me to indicate an attachment of any 

 vegetative organ along its surface or margin. 



Certain very important points as to the relations of the second, or oval, 

 boss to the leaf scar remain to be determined. At present it is not definitely 

 ascertained whether the oval boss, which in a few instances appears to be 

 closed at the base and barely contiguous with the transversely angular or 

 deltoid cicatrice, which I have called the leaf scar, is actually distinct from 

 that "scar" or whether it is organically connected therewith. The analogies 

 with the other Paleozoic Lycopodinem, especially some of the Sigillarioid 

 types, would, at first glance, lead us to inquire as to whether this oval boss 

 does not itself represent a part if not the wdiole of the foliar cicatrix. The 

 evidence in support of such a supposition lies largely in the presence of 

 the generally clear, narrow, very low, marginal rim of the boss and its 

 naturally suggestive similarity to the form of the cicatrices in some of the 

 Bothrodendra. Continuing the parallel with the Bothrodendroid or Sigilla- 

 rioid scar, it appears that in this case the trace at the upper end in the 

 central oval depression may be the vascular trace, while, by revei'sing the 

 position of the specimen, the punctiform ti'ace, wliich now seems either close 

 within or partly between the vanishing ends of the lower curves of the 

 oval, might be correlated with the trace just above the foliar cicatrices in 

 Sigillaria and Bofhrodendron. On the other hand, in opposition to the above 

 hypothesis, the interior details of the oval, the basal angular or deltoid scar, 

 and the superior trace in the bolster, as Avell as the form of the bolster 

 itself, seem to be arraigned. The oval boss comprises an outer zone about 

 5 mm. in width inclosing an oval depression. I have found no traces within 

 the latter except the umbilicate trace generally near the upper end, and 

 this shows on the cortex as a minute pit bordered by a raised carbonaceous 

 rim. In the impressions this trace causes a minute projecting point. Next, 

 the slightly raised transverse cicatrix at the base of the oval boss and on the 

 lower edge of the large boss showing a surface of separation, appears to be 

 supplied with a vascular trace, and occupies the position of a leaf in the Lepi- 

 dodendroid bolster. There are in a few instances even slight, though quite 

 uncertain and perhaps worthless, signs of the subfoliar appendages. Much 



