48 STIGMARIA FICOIDES. 



Length of each of the branches between the first and the second dichotomies. 



a. 5 feet e. 6 feet 



b. 3 „ 11 inches /. 4 „ 3 inches 



c. 3 „ 10 „ g. 7 „ 3 „ 



d. 4 „ 4 „ A. 3 „ 6 „ 



Length of each of the terminal undivided branches. 



6 inches 



I. 



4 feet 



II. 



7 „ 



III. 



6 „ 



IV. 



7 „ 



V. 



12 „ 



VI. 



9 „ 



VII. 



7 „ 



VIII. 



9 „ 



IX. 



2 feet 



X. 



3 „ 6 inches 



XI. 



4 „ 6 „ 



XII. 



3 „ 3 „ 



XIII. 



3 „ 



XIV. 



1 ,, 2 „ 



XV. 



4 „ 6 „ 



XVI. 1 



2 „ 



We do not know the full length of V, for it disappeared in a hard face of the 

 quarry, which, being under a roadway, could not easily be followed. 



Interpreting this specimen as I have explained Fig. 2 (Plate I), aided by the light 

 thrown upon both by the Figures 5 and 6 (Plate III), I conclude we have here no part 

 of the true aerial stem, which seems to have died down to its own base and disap- 

 peared. The central mass consists solely of the coalesced proximal ends of the four 

 primary roots. In this specimen the absence of every trace, either of rhizomatous 

 features, or of additional aerial stems ascending from these roots is also conspicuous. 



In each of the four roots the rootlet-scars are distinctly seen covering the eight 

 secondary branches a, b, &c. The ultimate divisions show them in the normal 

 form so characteristic of Stigmaria. How little the ramifications of this Stigmaria 

 have in common with the diagram published by M. Renault 2 need not be dwelt 

 upon. 



Still more recently a second and somewhat larger example has been dis- 

 covered in the adjoining Fall- Top Quarry, belonging to Messrs. Briggs and 

 Shepherd, not much above a hundred yards from, and resting upon the same 

 shaly bed, as that just described. The two specimens correspond in every 

 essential detail, only that several of the large roots in the Fall-Top fossil have not 

 yet been relieved of the thick mass of sandstone by which they are overlain. The 

 following measurements are taken in the same way as those on the preceding page : 



1 Since the xylograph 8 was prepared I have succeeded in laying this branch (xvi) bare, and tracing 

 its length to a distance of seven feet, when it became completely flattened, so that its upper and lower 

 surfaces were almost in contact. The additional length thus revealed is correctly represented in 

 xylograph 7. 



2 ' Cours de Botanique fossile,' Premiere anne'e, pi. 19, fig. 9. 



