34 



PALEOZOIC FOSSIL SPORES 



Spores assigned by Raistrick to type 

 D5 without much question belong to 

 Alati-s pontes. 



Remarks. — Only one species has been 

 described to date but there is little doubt 

 the group will receive far more recogni- 

 tion. It is highly distinctive and complex 

 enough that specific characters are easily 

 distinguishable. No doubt the character 

 of the bladders will lend itself to the 

 purpose. There is no possibility of these 

 forms being confused with unseparated 

 tetrad groups belonging to other genera 

 although illustrations which have been 

 published might lead one to think so. 



In addition to its recognition in the 

 Ruhr district and in Britain the genus 

 has been recognized in coals of the Illinois 

 basin by Brokaw and in Tennessee coals 

 by Bentall. These from America appear 

 to be specifically distinct and as yet un- 

 described forms. 



The generic diagnosis given above has 

 been constructed in the light of this 

 additional information, and while con- 

 siderably augmented over Ibrahim's mea- 

 ger description (1933, p. 32), it may be 

 improper to consider it as a generic emend- 

 ation. The type, of course, is the species 

 given below, which was first described 

 from the Aegir coal in the Ruhr. 



1. Alati - SPORITES PUSTULATUS (Ibrahim) 

 Ibrahim, 1933, Sporenformen des Aegir- 

 horizonts, p. 33, pi. 1, fig. 12. 



Sporonites pustulatus Ibrahim, 1932, 

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

 448, pi. 14, fig. 12. 



Alati - sporites pustulatus (Ibrahim) 

 Ibrahim, Loose, 1934, Inst. Palaobot. Arb.. 

 vol. 4, no. 3, p. 151, pi. 7, fig. 4. 



Type Ds Raistrick, 1937, Congres pour 

 I'avancement des etudes de stratigraphie 

 carbonifere, Heerlen, 1935, Compte rendu, 

 vol. 2, p. 911. 



Genus Reticulati-sporites ( Ibrahim, 

 1933) emend., S. W. and B. 



Plate 1, figures 7-7b 



Symmetry. — Spores, in essence, radi- 

 ally symmetrical ; some species are weakly 

 trilete and others show no indication of 

 their tetrahedral tetrad origin but are con- 

 sidered trilete in derivation because of 

 their shape. 



Shape. — Originally spherical or mod- 

 eratel}^ oblate ; compressed snores are cir- 

 cular disk-like, generally without prom- 

 inent folds. 



Sise. — Spores of various species range 

 from about 40 to 100 microns in diameter. 



Ornam^entation. — Coarsely and often ir- 

 regularly reticulate ; aside from the coarse 

 ornamentation the body wall may have a 

 variously smooth, punctate or finely re- 

 ticulate texture. In the ''alete" forms 

 reticulation may show a tendency toward 

 a spiral pattern ; in others it may be mostly 

 limited to the distal part of the spore. 



Haptotypie structures. — The trilete 

 structures may be weakly developed ; no 

 arcuate ridges are developed but the or- 

 namentation may sometimes be absent on 

 the proximal surface. The trilete rays 

 vary considerably in development and 

 length among different species. 



Spore coat. — Appears to consist often- 

 times of two membranes ; when present, 

 the outer one (perisporal?) is thinner and 

 more or less intimately connected with the 

 coarse reticulation; the inner (exospor- 

 al?) membrane is thicker and sometimes 

 irregular and excentric in its development. 

 The wall may appear thick, and yet be 

 quite translucent. 



Affinities. — The only spores of this gen- 

 eral or possible character known in fruc- 

 tifications are allied with Sphenophyllum. 

 Spkenophyllum spores are inadequately 

 known in the detail necessary for close 

 comparison, however, and considerably 

 more evidence is needed to form an opin- 

 ion as to the relationship of Reticulati- 

 sporites with other groups. 



Types C2, C3, F4, and Fg of Raistrick 

 (1934, 1935, 1937) and possibly also F„ 

 F2 (cf. Knox, 1938), Fg and F4, appear 

 to belong to Reticulati-sporites. Types 

 F5 and Fg and D,3 (Knox, 1938) are 

 more problematic. Type 8 of Millott 

 (1939) also belongs here and is most 

 closely related to R. facetus of species now 

 described. Knox' Type 5K may possibly 

 be similar to some species included in Re- 

 ticulati-sporites. Spores illustrated by 

 Knox (1939) from Fifeshire, figs. 49 and 

 50, unquestionably belong to Reticulati- 

 sporites. Unpublished forms of similar 

 nature have been found in Ohio coals by 

 Wilson and Brokaw, and they have also 

 been recognized in Iowa and Illinois and 

 Tennessee. 



Remarks. — Seven species are included 

 here under Reticulati-sporites, only one 

 of which represents a new name combina- 



