NATURAL SCIENCES OF PHILADELPHIA. 1 > 



beads have a pistil in the centpr, and others are wholly staminate, is, 

 there is greater axial vigor when the female flower is formed. Whenever the com- 

 mon peduncle (below the scarlet involucre) is weak, a pistil never appi 

 in that head of flowers. A few which seem strong neither hav tin m, but 

 the great majority of the strong peduncles are those which bear the female 

 blossoms. Another interesting fact is that the number of male flowers i 

 in those heads which also bear a female, than in those which are wholly 

 staminate. This seems to add to the point I made in my paper on Ambi 

 that after the flowers have been partially formed in embryo, and before 

 sex has been finally determined, the female flower, being primordially the 

 stronger, has the power of absorbing the mules or their partially formed 

 merits into its system. It is certainly remarkable that in both these instances 

 the number of male flowers should decrease in proportion to the existence or 

 vigor of the central female one. 



The male and female flowers of Euphorbia fulgens are formed much alike. 

 The female occupies the center, and seems really but a prolongation of the 

 main stem, on the top of which is an articulation from which the ovarium 

 springs. The capsula readily falls from this articulation when mature. From 

 the base of the female central peduncle spring weaker peduncles, color! 

 appearing indeed almost like filaments, articulated at about the same height 

 as the female, only above the point bearing a short filament and anther the 

 caduceous part before referred to. No one can fail to see the correspondence 

 of plan in these, different parts, and I think that nothing but the favorable 

 position in the direct line of axial vigor made the central flower a female one. 



Cases occasionally occur in which a tolerably strong head of wholly male 

 flowers will develop the central axis into a pedicel almost as lung and vigorous 

 as those which bear female flowers. But the flow of vital force if 1 am correct 

 in using this term not being quite sufficient, the- final goal of natural per- 

 fection in the female form was not reached. These cases do not occur often, 

 but are well worth looking for, as they show so clearly the dividing line be- 

 tween the forces which govern the male or female sex. 



Note on the Relations of SYNOCLADIA, King, 1849, to the Proposed Genus 



SEPTOPORA, Prout, 1858.* 



BY F. B. MEEK AND A. H. WORTHEN, 



Of the Illinois State Geological Survey. 



Not having studied the Polyzoa of our rocks, it was only recently that we 

 noticed the remarkable agreement between the fossil from the Chester division 

 of the Lower Carboniferous, on which Dr. Prout proposed to found a genus 

 Septopora, and the common Western Coal-measure species, that has been by 

 some referred to the European Permian species, Synocladia virgulacra. the type 

 of Prof. King's genus Synocladia. In identifying this fossil, from beds in Kan- 

 sas referred by him to the lower Permian, with S. virgulacea, Prof. Swallow 

 noticed that it differs from the foreign species in having only two, or, on some 

 parts, apparently three,f rows of cellules to each of the longitudinal branches, 

 instead of from three to five rows, as in the latter; and although he referred 

 the Western species doubtfully to S. virgulacea, he proposed for it the pro- 

 visional name, S. biserialis, in case the differences noted should be considered 

 of specific importance. J Prof. Geinitz, however, did not consider these differ- 

 ences of full specific value, and referred the species to S. virgulacea.% 



* Transac. Acad. Sci. St. Louis, Vol. I, p. 448, pi. 18, J Bg. 2, 2 a, b c, 1858. 



+ It is only immediately below the bifurcations of the larger stems that the pore re- 

 arranged that they might be counted so as to appear to make three roua. the proper 

 number of rows being only two. 



X Trans. Acad. St. Louis, Vol. I, p. 179, 1838. 



5 Carbonf. und Dyas, in Nebraska, p. 70, 1866. 



1870.] 



