224 Reports and Proceedings. 



Professor T. Rupert Jones remarked on the analogy between the passage from the 

 Chalk to the Eocene Tertiaries, as supposed to be exhibited in the South of Prance 

 and in the Nebraska territory of America. He pointed out that the Cretaceous beds 

 of France having been deposited, not in one sea, but in separate sea areas, they were, 

 of course, difficult of correlation. 



2. " On the Structure and Affinities of Sigillaria and allied genera." 

 By W. Carruthers, Esq., F.L.S., F.G.S. 



The author indicated the characters of the medullary rays of dico- 

 tyledonoixs stems, and stated that these stems have a vascular hori- 

 zontal system connected with the axial organs, in which respect the 

 dicotyledonous and acrogenous stems agree. The woody columns of 

 Stigmaria and Sigillaria are destitute of medullary rays, the struc- 

 tures previously described as such being the vascular bundles run- 

 ning to the rootlets and leaves. Hence the author concluded that 

 Sigillaria is a true cryptogam, a position supported by the characters 

 of the organs of reproduction as described by Goldenberg. The 

 paper concluded with an enumeration of the forms of fruits belong- 

 ing to Sigillaria and its allied genera, with indications of the exist- 

 ing forms to which they most nearly approach. 



Discussion. — Professor Morris insisted on the necessity of the student of fossil 

 botany being thoroughly acquainted with modern botany also. It was from speci- 

 mens discovered many years ago by Mr. Prestwich that the true nature of the 

 Stigmarice had been discovered, and he quite agreed with the author in regarding 

 them as cryptogams, and in no way connected with gymnosperms. The abundance 

 of cryptogamic spores in coal was hardly at present appreciated. There were some 

 varieties of coal almost exclusively composed of such spores. 



3. " On the British Species of the Genera Climacograpsus, Diplo- 

 grapsiis, Dicranograpsus, and Didymograpsus. By H. Alleyne Nichol- 

 son, D.Sc, M.B., F.G.S. 



The author stated that all the genera referred to in this paper 

 appear to be exclusively of Lower Siluidan age, — Climacograpsus and 

 JDiplograpstis occurring almost throughout the Lower Silurian series, 

 whilst the other two genera belong chiefly to the Llandeilo series of 

 rocks, or to strata of corresponding position out of Britain. 



The British species of the above genera admitted by the author 

 are : — 



Climacograi^sus teretiusculus, His. 



hicornis. Hall. 



. ■ tuherculatuff, Nich, sp. n, 



Diploffrapsus pristis, His. 



mucronaJus, Hall. 



. Wlntficldii, Hall. 



Harknessii. Nich. 



confertus. Nich. 



comda, Gein. 



• palmeiis. Barr. 



acuminatus, Nich. 



veaiculo-vs. Nich. 



■ pristiiiiformis. Hall. 



The paper included descriptions of the sujoposed embryonic states 

 of several of the species. 



Discussion. — Mr. Carruthers observed that he saw no reason, from what Dr. 

 Nicholson said, for changing his opinion that Diploc/rapaus vesiculosus was a bad 

 species. The enlargement of the axis was known in other species of the genus. 

 The notion that this enlarged axis might be a " Grapto-gonophore " was more un- 

 likely than any of Dr. Nicholson's former ideas on this subject. As to the anatomy 



Diplograpsus tamariscus, Nich. 

 pusillus, Hall. 



nodosus, Harkn. 



pinnatus, Harkn. 



■ , sp. 



Dicranoc/rapsus ramosus, Hall. 

 Didymograpsus Murchisoni, Beck. 



affiais, Nich., sp. n. 



diraricatus. Hall. 



— — ■ anceps, Nich. 

 flaccidus, Hall. 



sextans, Hall. 



