Johnson — The Occurrence of Arch(eopteris TschermaJci, Sttir. 139 



Archwopteris TscJiermalil differs from most species of the genus in its 

 dichotomous frond, each lialf of which is simply pinnate, or basally sitb- 

 bipinnate. 



Formation. — Upper Devonian beds, Kiltorean, Ireland. In the same slab, 

 alongside of Arc/iceopten's hibeniica, and Bothrodendron kiitorkense, Haughton, 

 sp., which latter overlaps and partly liides it. 



This fertile Irish specimen is of interest, as it extends the range of 

 ArchcBopteris Tsc/ierwciki, Stur, both in space and time, and shows tliat 

 Archseopteris extended upwards into the Oulm, and, like so many other 

 Palaeozoic plants, possessed a bifurcating frond. My drawing of the fertile 

 specimen was made before I had seen Stur's figure of A. TschermaJci, with 

 which Nathorst suggested comparison. The identity of the two figures is 

 striking, and helps to justify the allocation of the specimen to A. Tsohermaki^ 

 rather than the creation of a new species of Avcbaeopteris. 



Collection. — Botanical Division, National Museum, Dublin. "B.D. 10." 



Archseopteris hibernica, var. minor, Cr^pin, and A. Eoemeriana, Gropp. 



Some of the Kiltorean specimens of Arehaeopteris show pinnules less 

 imbricate than usual, and not more than half the ordinary size. Crepin 

 noticed in the Brussels Museum in 1874 such a smaller specimen in a slab 

 sent from Kiltorean twenty years previously, and regarded it as probably 

 identical (" une forme semblable ") with his A. hibernica, var. minor, found 

 in the Evieux beds in Belgium. His figure shows two pairs of over- 

 lapping unstalked pinnules, with decurrent base of attachment, quite like 

 a Kiltorean specimen in the Botanical Division of the National Museum, 

 Dublin. 



Crepin believed that the (Ci/clopteiis) Archceopteris Eoemeriana of Goppert 

 from Aachen (really not far from Evieux, though the two localities are in 

 different countries) was his A. hilernica var. minor, and that the name of 

 A. Eoemeriana Gopp., sp., ought to be suppressed. Now A. Eoemeriana, 

 Gopp., as originally described, shows two alleged points of difference from 

 A. hibernica. Its pinnules do not overlap, and are much smaller than those of 

 A. hibernica as usually found. There are, too, no inter-pinnate or rachidial 

 pinnules, according to Goppert and Potonie. There are specimens in the 

 Dublin Museum which show such non-imbxicate, smaller, stalked pinnules, 

 but they also show distinctly the presence of aphlebioid rachidial pinnules. 



D. Stur: Die Culni-Floia, (s. 57 etseq., Taf. xii., fig. 1, and Taf. xvi., fig. 1). 



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