554 THE AMERICAN MIDLAND NATURALIST 



attachment was not demonstrated in either case. The importance of such attach- 

 ment was not then realized, and it is probable that the specimens studied by 

 both of these authors were attached to a cone axis in the true Lepidocarpon 

 fashion. Miss Reed has recently demonstrated such attachment for other Harris- 

 burg specimens by means of an adequate series of tangential slices described 

 at the 1939 meeting of the Paleobotanical Section. The importance of pedicel 

 attachment in the lepidocarps is emphasized below in connection with the 

 discussion of Illinio carport. 



Both Noe and Krick identified their lepidocarp material as Lepidocarpon 

 lomaxi Scott. This specific identification is doubtful, however, because the 

 similarities mentioned by Krick concern chiefly the size of the seed body. 

 Without supporting evidence this cannot be regarded as positive proof of 

 specific identity. The histological details particularly must also be carefully 

 considered. The Harrisburg material appears to be significantly younger than 

 the "Lower Coal Measures" specimens studied by Scott. 



The sporophylls described by Fredda Reed (1936) were not specifically 

 identified. They appear to correspond with immature and abortive megasporan- 

 gia such as Scott reported for L. lomaxi. However, the sporangium wall had a 

 sclerotic rather than a prismatic external layer of cells. This may be a feature 

 of considerable significance in lepidocarp evolution, inasmuch as it indicates 

 the loss of a primitive character well represented in the lomaxi group. 



The writer described two new species belonging to the Lepidoearpaceae in 

 1938 (Schopf, 1938a). One (L. mazonense) is a form common in the Mazon 

 concretions above the Colchester (No. 2) coal in Grundy and Will counties 

 wnich resembles in many respects the generalized type traditionally known as 

 Lepidophyllum majus. Its reference to Lepidocarpon was definitely established 

 although it is not certain that this species is distinct from earlier described but 

 less adequately understood forms. Lepidophyllum majus itself is confused taxo- 

 nomically because the type is a poor specimen with the seed body missing; it 

 was originally designated Filiates (Glossopteris) dubius by Brongniart (1822), 

 and its name was later changed in the Prodrome (1828, p. 87). It would prob- 

 ably be impossible to prove that the Mazon form is cospecific with the type, 

 even if such were actually the case. Certainly some of the specimens referred 

 to L. majus are not cospecific with Lepidocarpon mazonense, although there is 

 no reason for believing them to be generically distinct. Probably Brongniart's 

 species will pass into disuse because of the inconclusive nature of its type and 

 the consequent doubt as to its accurate specific definition. 



A brief description of a new type of lepidocarp seed was presented in the 

 same publication (Schopf, 1938a). This differs significantly from the genus 

 Lepidocarpon and a new generic name, llliniocarpon, was given it. In trans- 

 verse sections through certain parts of the seed body it closely resembles 

 Lepidocarpon, but a qualitative and diagnostic difference appears in the manner 

 of sporophyll attachment to the fertile branch. This distinction is commonly 

 shown in longitudinal sections, and single transverse sections of either Lepido- 

 carpon or llliniocarpon cannot be counted on to provide conclusive evidence of 



