Ik ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 500 



axis and the short pinnae is more like A. quercifolia than any other 

 species of Alloiopteris . Measurements: pinna k mm long, 2 mm wide, 2 

 mm apart. Pinnules 0.8 mm long. 



Dactylotheca aspera (Brongniart) Zeiller 

 Text fig. 5D; pi. 3, figs. 1-3 



Description . — Frond two (or three) times pinnate. Pinnules 9 mm 

 long, 2.5 mm wide, attached 3.5 to k mm apart; shape and attachment 

 pecopteroid, slightly restricted at the distal side of the "base. Pin- 

 nules lobed with five lobes on each side, tip rounded, lobes rounded 

 and about 1.3 mm wide. Venation badly preserved, but apparently one 

 midvein with two unforked lateral veins per lobe„ Two to six sporangia 

 per lobe; sporangia elongated, small, 0.8 x 0.2 mm. 



Discussion . — This species bears pecopteroid pinnules with elon- 

 gated, solitary sporangia that do not show any trace of an annulus. The 

 arrangement of the sporangia is typically that found in the fructifica- 

 tion genus Dactylotheca Zeiller. Dyotheca Hartung has also been used 

 for these forms, and they are similar to Renaultia Stur in general ap- 

 pearance. The fragmentary specimens at hand, which are preserved in a 

 relatively coarse matrix, do not allow a thorough revision. Thus for 

 the present paper, Dactylotheca is used. 



Pecopteris aspera is known from the Lower Carboniferous to the 

 lower part of the Westphalian A (Remy and Remy, 1959, p. 63). Our speci- 

 mens compare closely with the figures of the same species from the 

 Namurian A of Czechoslovakia (Purkynova", 1970, pi. 39 9 figs. 6, 6a). 

 There is some similarity with Pecopteris (Senftenbergia) namurica Pur- 

 kynov£ (1970, p. 21^, pi. k0 9 figs. 3, 3a, 3b). There is some overall 

 similarity to Pecopteris (? Dactylotheca) oregonensis Arnold from the 

 Namurian of Oregon. However, the latter species has smaller pinnules 

 and thicker sporangia. Our specimens can also be compared with Renaultia 

 gracilis. The position of the sporangia is very similar to that in 

 R. gracilis but the sporangia are more elongated in our specimens. 



NOEGGERATHIALES 

 ( ? Progymnos perms ) 



The Noeggerathiales are a rare group of uncertain systematic po- 

 sition. The few forms belonging to this group are normally found in 

 small numbers and as fragmented specimens. In the Spencer Farm Flora, 

 however, they are the second most common group of plants after the 

 Pteridosperms. As the geologic position of this flora (ravine deposit) 

 indicates an "extrabasinal," or upland, flora and because Noeggerathiales 

 are extremely rare in roof-shale floras (l in ^000 specimens in the Il- 

 linois Basin), it is concluded that the Noeggerathiales were upland plants 



In the Spencer Farm Flora, three species, Lacoea seriata, Palae- 

 opteridium reussii , and Gulpenia limburgensis , have been assigned to the 

 Noeggerathiales. Lacoea is without a doubt a noeggerathialean cone, and 

 Palaeopteridium has generally been regarded as a member of this group. 

 However, we are tentatively associating Gulpenia with the Noeggerathiales 

 for the first time. 



