. Maryland geological survey. t the sporangia couldhardly have dehisced before fossilization, since each tiny rock cavitywhich represents these fructifications is packed with the spores. In someof the impressions there are faint transverse lines on the matrix as if theymarked the line of demarcation between successive pairs of sporangia;bearing branches, and in one case the vein upon which the fructificationwas borne can be traced the entire length of the fructification, clearlyindicating that it is not a gigantic simple sporangium but an aggregate 218 Systematic Paleontology of sporangia comp
. Maryland geological survey. t the sporangia couldhardly have dehisced before fossilization, since each tiny rock cavitywhich represents these fructifications is packed with the spores. In someof the impressions there are faint transverse lines on the matrix as if theymarked the line of demarcation between successive pairs of sporangia;bearing branches, and in one case the vein upon which the fructificationwas borne can be traced the entire length of the fructification, clearlyindicating that it is not a gigantic simple sporangium but an aggregate 218 Systematic Paleontology of sporangia comparable to that of the modern genus Scliizcea. Theseare both figured (x4) on pi. xxii. With regard to the botanical affinity of this species the writersconvictions are indicated in the generic name. No modern group offerns fulfils the conditions as does the family Sehizseacese. The fossilfern is identical with various modem tropical members of this familyin vegetative habit, no other modern ferns known to the writer resembling. Fig. 2.—Restoration of a frond of Schizseopsis americana Berry, about four-fifths natural size. it in the character of the fronds except the genus BJiipidopteris of thePolypodiacese, which has a quite different habit and type of venation is closely similar to Schizcea. The fructifications are sim-ilarly borne and the spores are similar in form and markings to those ofthe closely allied modern species of Lygodium and Aneimia. It is be-lieved that the combination of close agreement in vegetative characterswith a similar close agreement in fructification characters, in so faras they are determinable from the nature of the material, justifies thereference of these ferns to the family Schizseacese, a family which ontheoretical grounds we would expect to find represented in the Lower Maryland Geological Survey 219 Cretaceous. Whether the detailed organization of the fructifications con-forms to that which obtains in the modem members of the
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