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ME. P. MARTIN DUNCAN ON THE GENERA HETEROPHTLLIA, 
completed. When the first kind of bud has more than five septa the resulting corallite 
grows like the parent. Diameter of corallites from -To inch to inch. 
Locality. Teignmouth. Devonian limestones. 
The generic characters of Battersbyia may be altered in consequence of the specific 
characteristics of the new forms : — 
Corallum fasciculate and branching. Corallites tall, cylindrical, unequal in size and 
distance. Septa numerous and following no apparent cyclical order. 
Endotheca very abundant ; it is vesicular, and there are no tabulae. Epitheca, costae, 
and ccenenchyma wanting. The wall is stout ; and the septa spring from wedge-shaped 
processes. The columellary space is occupied by vesicular endotheca. Gemmation 
extracalicular, and calicular from buds having only five septa. 
Being satisfied that there is no ccenenchyma in Battersbyia grandis and Battersbyia 
gemmans, and that it is simulated in Battersbyia incequalis, Ed. & H., by an investing 
and incrusting Stromatopora, the removal of the genus from the Milleporidce , where it 
had been placed somewhat provisionally by MM. Milne-Edwards and J ules Haime, is 
absolutely necessary. 
The corallum in every species is fasciculate ; and the unequal size of the corallites is 
determined by the method of gemmation. In the case of Battersbyia gemmans the dif- 
ference in the size of the corallites is excessive ; and it is very probable that its peculiar 
gemmation is witnessed in the other species. The buds which develope more than five 
septa appear to grow into corallites, which are destined to bud again from the external 
wall ; and the buds which develope five septa soon produce other buds from their inter- 
septal loculi, the buds thus developed resembling the multiseptate corallites. This 
curious alternation of gemmation has not been observed in any other genus ; but it is 
remarkable that the Heterophyllice with six septa should be related to Heterophyllice 
with numerous septa. 
The genera Heterophyllia and Battersbyia have much in common. They have a stout 
wall, a vesicular and dissepimental endotheca, delicate septa, very irregular in their 
number, and neither tabulae, epitheca, nor a quaternary septal arrangement. The genus 
JBattersbyia has nothing to ally it to the Bugosa ; and Heterophyllia has in some of its 
species the solitary large septum or a vacancy where a septum should be, which is so 
often observed in the Cyathophyllidce. Its costae and endotheca connect the genus with 
the mesozoic and recent Astrceidce ; and that this family, unrepresented in palaeozoic 
strata, is foreshadowed by the genera now under consideration is very evident. 
The costae of Heterophyllia mirabilis are the most extraordinary ever recorded, and 
they are unlike those of any other species of coral. 
There is nothing unusual in the irregular septal development of Battersbyia ; for it is 
noticed in the Liassic fasciculate Astrceidce ; and whilst this genus points to the genera 
Pentaccenia , Calamophyllia, and Thecosmilia, Heterophyllia may be likened, faintly it 
is true, to Bhabdophyllia. 
It would appear necessary to associate the genera Battersbyia and Heterophyllia 
