274 Wilhelm Bock 1969
The megasporophyll of the new species appears to be also of primitive structure, distinguished by having microphyllous leaves formed bud-like around a second order shoot axis, equipped with small seed scales, evolving into one or two seeds. The large number of seed scales supports a phylogenetic trend toward an increased seed production. The separation of the microphyllous leaves along the bract from those of the axillary buds, registers a clear trend of transition from separate fertile organization to bisporangial cones. The presence of an entire inflorescence, apparently devoid of ovulate components should be a convincing proof.
To demonstrate the ontogenetic development of the fertile structure from various stages of cone growth fig. 461, a-d illustrates the bisporangiate cone of the new species. It is fundamentally comparable with cycadeoidean cones so well shown in the excellent recent work of Delevoryas (1968, p. 124, fig. on p. 125) wherein the actual microsporangial structure of this group is clearly explained. The cycadeoidean cone is likewise a shoot, the fundamental foliar appendages (bracts or leaves) being transformed into fertile appendages (fig. 463). The so-called seminal scales are believed to be normal seed scales, each apparently supported by a single or more sterile scales, all derived from base leaves. The origin of the cycadeoidean cone is already largely obscured by an extended lineage of changes, which may have involved a period as long as 30 million years. In another interesting illustration Delevoryas (pl. 3, fig. 16 ) reveals a cone with abnormal seeds, which he stated "to resemble mature seeds at first glance." The distortion of the cone suggests that the relatively small number of seeds, if they are such, may be a recapitulation of a preceding phylogenetic trend. To afford a more convenient comparison fig. 461,e (of this text) is supplemented by a small drawing of Delevoryas abnormal cycadeoidean cone.
Another problem was seemingly caused by the second order shoots in our new species (fig. 462). There appears to be no evidence on hand that the Cycadeoids indulged for long in such a structure. It is believed that the multiple cone system has been abandoned long ago, but an occasional double cone insertion should be a welcome evidence. Looking at fig. 462 once more, it should be noted that the terminal cone of both specimens (A and B) is subtended by a base leaf and they are growth of second order just as the axillary one of the new species. Both cone systems have in common the arrangement of the spiral-dichopodial base leaves around the first:order shoot and the terminal second order shoot with its base leaf modification into microsporangial appendages and seed scales. Obviously abandoned by the cycadalean inflorescence are cones with solitary seeds, axillary cones of the base bracts and the growth of microsporophylls on bracts, not included in bud enclosures.
The relationship of the new species Triassiflorites to the cycadalean group is still unsettled. Cycadean microphyllous cones are similar in skeletal structure, but all groups appear to be monosporophyllous although this may be favorable as a mark of primitiveness.
As a final conclusion it may be stated that the new species Triassiflorites represents a primitive cycadophytian transition type toward the Bennettitales, particularly the cycadeoidean group, and also points toward a transition of bisporangiate growth.
Description of the genus and family being the same as the description of the species, enumerated in paragraph "structure". Genotype: Triassiflorites grandiflora.