±66 G. M. E filers — New Species of Tetracoralla. 



ular-shaped funnels. In one interseptal space, a funnel 

 is formed by the depression of a tabula towards one of 

 the angles made by a denticulate septum and the wall of 

 the corallum. A few funnels are produced by the de- 

 pression of the tabulae towards points on the wall that 

 are intermediate between the lamellif orm and denticulate 

 septa. 



The appearance of simple dissepiments is sometimes 

 produced by the branching of the tabulae near the wall of 

 the corallum. True dissepiments, however, probably 

 never were formed. 



The paleontological museum of the University of 

 Michigan contains another specimen of Heterolasma 

 foerstei, which was found by Dr. Carl Rominger near the 

 village of Detour, Chippewa County, Michigan. 



The specimen, which, with little doubt, was collected 

 from the Manistique strata, is silicified and more poorly 

 preserved than the type specimen. Most of the lower, 

 short conical part of the corallum and all of the horizon- 

 tally expanded upper part have been broken off. 



The broken and somewhat compressed specimen dif- 

 fers in structure from the type specimen only in the 

 preservation, number and arrangement of certain septa. 

 The cardinal septum, which is poorly indicated in the 

 type specimen, is well shown in the calyx of this speci- 

 men. The positions of the two alar septa and the 

 counter septum are also more or less well indicated. 

 Fifty-two lamelliform, secondary septa seem to have 

 been present originally ; eleven are shown in each of the 

 counter quadrants, fifteen in one cardinal quadrant and 

 fourteen in the other. A fifteenth septum is not shown 

 in the last mentioned cardinal quadrant, owing to its 

 probable removal with a small part of the wall of the 

 corallum. The tertiary, denticulate septa and the low, 

 quaternary ones are more or less poorly preserved, 

 owing to solution and silification of the corallum. 



Zaphrentis patens Billings, 2 which occurs in the Anti- 

 costian (Jupiter River) strata of Cormorant Point, 

 Anticosti, seems to be congeneric with Heterolasma foer- 

 stei. This relationship is indicated by the more or less 

 close similarity in the shape of the coralla and in the 

 character of the septa and tabulae. 



2 This species was described first by Mr. E. Billings (Can. Nat. Geol., 

 new ser., vol. 2, p. 430, 1865) and later by Dr. L. M. Lambe (Contr. Can. 

 Pal., Geol. Surv. Canada, vol. 4, pt. 2, pp. 119-120, 1901). 



