RAISTRICKIA 



55 



Genus Raistrickia S. W. and B., 

 gen. nov. 



Plate 3, figures 18-18b; text figure 3 



Symmetry. — Spores radial; trilete. 



Shape. — Sperical to slightly flattened in 

 transverse plane and slightly triangular. 

 Little preference as to plane is shown by 

 compressed specimens. 



Size. — Spores of diiTerent species vary 

 from about 40 to 90 microns in mean di- 

 ameter. 



Ornamentation. — Characteristically ver- 

 rucose or spinose ; spines when present 

 are generally heavy, abruptly truncate, 

 blunt tipped- Close observation often 

 shows the spine tips to be minutely dis- 

 sected into two to six terminal papillae. 

 The prominences of verrucose forms are 

 similar to the spines but shorter. Except 

 for the trilete structure, features of em- 

 phytic ornamentation extend fairly evenly 

 over the whole spore surface. 



Haptotypic features. — Trilete rays va- 

 riable in length as in Punctati-sporites ; 

 generally inconspicuous, lips unorna- 

 mented. Rays sometimes slightly undu- 

 lant due to proximity of spine bases ; 

 arcuate distinctions absent. 



Spore coat. — Usually of moderate 

 thickness (two to six microns) perisporal 

 membrane lacking. 



Affinity. — Typical forms of Raistrickia 

 are without doubt filicinean. Spores of 

 Senftenhergia plumosa, as identified by 

 Radforth (1938), agree with these of 

 Raistrickia, and similar schizaeaceous 

 sporangia obtained by Andrews and 

 Schopf from shale above Illinois coal No. 

 6 also contain spores of this type. How- 

 ever, the spores of a form identified as ^. 

 pennaef or mis by Radforth (1939) show 

 rather different features, and those of 

 6". sturi do not appear congeneric with 

 Raistrickia. Although the general rela- 

 tionship cannot easily be doubted, the 

 specific features do not permit easy cor- 

 relation and Senftenhergia and Raistrickia 

 no doubt represent generic groups of 

 somewhat different circumscription. 



Raistrick's types E3 and E^ (Raistrick 

 and Simpson, 1933 ; Raistrick, 1934, 1935, 

 1937) belong in Raistrickia. His Eg type 

 is particularly characteristic. That rep- 

 resented as E^ by Knox (1938), how- 



ever, is somewhat questionable. Forms 

 Knox (1938) illustrates as D3 and Dg 

 probably belong in this genus. Reinsch 

 (1884) has illustrated only three forms 

 which belong to this group without much 

 doubt. These are described under his 

 diagnoses 52, 308, and 588 from central 

 Russia and from Zwickau, Saxony. The 

 form illustrated by Thiessen (1920) in 

 plate 61, figure B, from Benton, Illinois 

 (probably the Herrin No. 6 coal), is 

 characteristic of Raistrickia; that shown 

 above it in horizontal thin section may 

 likewise belong here but it is impossible 

 to be sure. The two illustrations show 

 the inadequacies of thin sections for iden- 

 tification of spores. 



Remarks. — Five species previously de- 

 scribed are assigned to Raistrickia. These 

 forms are widely distributed as may be 

 inferred from the preceding discussion. 

 None of these previously named are 

 very suitable for designation as a type, 

 however, inasmuch as the more typical 

 form, which particularly seems generic- 

 ally distinct from Punctati-sporites, has 

 not previously been formally designated 

 although it seems fairly common. Fur- 

 thermore, inadequacies in the previous 

 descriptions and illustrations also mih- 

 tate against selection of any of them as 

 types for this genus. The species de- 

 scribed below, Raistrickia grovensis sp. 

 nov. is therefore designated as the type. 



1. Raistrickia (?) abditus (Loose) S. W. 

 and B., comb. nov. 



Sporonites abditus Loose, 1932, Neues 

 Jahrb.. Beilage-Band 67, Abt. B., p. 451, 

 pi. 19, fig. 53; 



V errucosi-sporites abditus (Loose) 

 Loose 1934, Inst. Palaobot. Arb., vol. 4, no. 

 3, p. 154. . 



2. Raistrickia fibratus (Loose) S. W. and 

 B., comb. nov. 



Sporonites fibratus Loose, 1932, Neues 

 Jahrb., Beilage-Band 67, Abt. B., p. 451, pi. 

 19, fig. 52. 



Setosi-sporites fibratus (Loose) Loose, 

 1934, Inst. Palaobot. Arb., vol. 4, no. 3, p. 

 148. 



3. Raistrickia grovensis Schopf, sp. nov. 



Text figure 3 



Description. — -Spore rounded triangular in out- 

 line, about 50 microns in diameter. Orna- 

 mented with numerous short (3-5 /x) broad 

 (2-6 iJi) blunt tipped spines, which by juxtapo- 

 sition sometimes appear to be mutually attached. 

 Rays 15-20 ix long, slightly undulating, lips not 

 raised but forming a narrow margin on either 

 side of the suture line. Wall somewhat vari- 



