. Annals of the New York Academy of Sciences. Science. 66 ANNALS NEW YORK ACADEMY OF SCIENCES. Silicified specimens of Enterolasma strictum are very abundant in the New Scotland limestone, but they are not sufficiently well preserved to use in grinding, or in cutting sections. Numerous specimens of various sizes and ages have been carefully studied. The general manner of development is found to agree with that observed in the Ordovicic and Siluric corals. The septa unite at the center more distinctly than in any of the preceding species. The pseudocolumella thus formed is not exactly solid, bu
. Annals of the New York Academy of Sciences. Science. 66 ANNALS NEW YORK ACADEMY OF SCIENCES. Silicified specimens of Enterolasma strictum are very abundant in the New Scotland limestone, but they are not sufficiently well preserved to use in grinding, or in cutting sections. Numerous specimens of various sizes and ages have been carefully studied. The general manner of development is found to agree with that observed in the Ordovicic and Siluric corals. The septa unite at the center more distinctly than in any of the preceding species. The pseudocolumella thus formed is not exactly solid, but it is much more substantial than that found in Enterolasma caliculum. In many specimens when looked at from the top it appears to be hollow or approaching in appearance the well-developed inner wall of such a species as Hapsiphyllum Another feature in which this species differs from those discussed in the previous chapter is in the manner of development of the small tertiary septa. In all the geologically earlier species the tertiary septa (secondary lamellae of Hall) arise as low, free ridges between adjacent primary and secondary septa. They remain free and unattached to any of the primary or secondary septa throughout their development. In Enterolasma strictum a different condi- tion is found. This condition is mentioned by Hall when he states that the alternate septa frequently coalesce with the primary septa, and is clearly shown in the sectional views of figures 1 and 2. Of these two views figure 2 is taken just below the base of the cup, while figure 1 is taken farther down in the corallite. This species was taken by Simpson as the type of his genus In the large number of specimens from the New Scotland limestone beds examined in the present study only one presented the appearance in the figure by Simpson accompanying his generic description of Enterolasma and this was a large individual considerably above the average size. The specimens exa
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