48 



BULLETIN 65, UNITED STATES NATIONAL MUSEUM. 



Gurley, in bis uiannscript. adas to the descriptions of Hall and Siiencer in 

 the following note : 



Two specimens from the Niagara formation, at Hamilton, Ontario, are 

 figured, showing the blunt tootblike bodies and the apparently dentate mar- 

 gin. While the appearance much resembles thecse, it is impossible to make 

 a positive statement on the material available. 

 From a fairly large series of good specimens we derive the following data 

 on this important species : 



The rhabdosome is arborescent in form ; the branches divide dlchotomously 

 at irregular intervals, forming initial angles of 50°-60° but becoming later 

 subparallel; of large dimensions (maximal length of largest fragment observed 

 14 cm., width of another IT cm.), the stem near base 5 mm. thick, the branches 

 quite uniformly 3 mm. The branches diminish hardly toward the distal ex- 



€0 



61 



h 1 %!^4 



Pics. 60-62. — Inocaulis plumulosus Hall. 60, Portiox of a branch, x o ; 61, 

 Distal portio.v of branches showing tubclak branciilets and i.mpressions of 

 THEIR apertures ; 62, Terminal portion of a branch. 



tremlties which are bluntly rounded. The stem is apparently smooth, the 

 branches are thickly .set with short tubular processes which project about 1 

 mm. from the body of the branch, are of uniform width, directed upward and 

 distally slightly bent backward and number, counted along the margin, about 

 14 in 10 mm. On specimens where the body of the branch has weathered away, 

 exposing the apertures of the reverse side, they are seen to be distributed about 

 equally over the whole branch, being approximately arranged in quincunx and 

 numbering about five in the width of the stem. At the extremities of the 

 branch they form dense tufts. 



R('»i(irk.s. — The general habitus of /. phnniilosa can be best described by a 

 comparison with a Lepidodendron or a Lycopodium ; it not only resembles 

 these i)]ants in the mode of its branching and the uniformly wide, blunt ending 

 branches, but also in their scaly appearance. 



Hall's original and later improved figures give a good conception of the gen- 

 eral appearance of the form. A more complete specimen from the Lockport 



