222 Eepoet op the State Geologist. 



with stipes, the same covering each • other, while those of D, 

 Buedemanni, . Gurley, appear rather plain. 



The Funicle and the Central Disc. 



In all known compound fronds, where the branches radiate 

 from a center, their bases are connected by a common branch 

 which has been termed by Hall the ^' funicle." He found that 

 this connecting stem within the points of bifurcation is not cel- 

 luliferous, more cylindrical and apparently more solid, the test 

 being, probably, thicker and the common canal less developed 

 than in the other parts of the axes. The figures of Hall and 

 Herrmann represent the funicle as a short cylindrical body, 

 slightly thicker than the axes of the branches Only in Grapto- 

 lithes octonarius^ Hall, we see a small expansion of the funicle and 

 a small round node called a "rootlet," by Hall. 



The funicles of the two Diplograptidse appear, if strongly com- 

 pressed, as small, oblong, black spots with round ends, from which 

 most axes spring (cf . PL I, figs. 1, 9 ; PL II, figs 3, 4) ; in a few 

 cases they are extended to cylinders, similar to those described by 

 Hall. In some specimens, however, the funicle is so well preserved 

 that I have been able to make out its finest details (cf. PL I, figs. 

 4, 6). By these it is made evident that the funicle of Diplograp- 

 tus was a chitinous vesicle, tapering to the two opposite initial 

 points of the main bundles of axes (PL I, Q.g. 6). Yertically to 

 this main extension, where two other bundles leave, the funicle is 

 more or less expanded, sometimes so much as to appear quadran- 

 gular (PL T, fig. 4). In the excellent specimen represented in PL 

 I, fig. 4, and PL II, fig. 3, the funicle is burst open and the inside 

 of the almost square base becomes visible. The pits, scattered all 

 over it, apparently lead into axes. The chitinous test must have 

 been very solid, as the excellent state of preservation of this small 

 organ proves. The latter attracts attention by its deep black 

 color in compressed fossils and by its strong sculpture in speci- 

 mens preserved in relief. 



The funicle has been found to be surrounded by a more or less 

 expanded chitinous disc or cup, the "central disc," of Hall. We 

 have observed that Hall regarded this organ as formed of two 

 laminae. He finds it obviously adapted to give strength and 

 support to the bases of the stipes, as in some forms it extends 



