

Vol. 67.] THE AVONIAN OF BURRINGTON COMBE. 377 



No specimens illustrating this mutation have been found at 

 Burrington, where Caninia is not definitely known above C . 



It is interesting to point out that in Belgium, where the gens 

 probably originated, stage 2 (y. s.) is the highest stage reached in 

 Z x (Calcaire de Landelies). 



Endophyllam priscum (Minister) Freeh, 1 from the lower part of 

 the Upper Devonian, is a Caninid that reaches the stage 2. The 

 early stages, however, of this coral resemble those of the next 

 described species, and it cannot therefore be regarded as a member 

 of the gens of C. cylindrica. 



It is interesting to notice that similar stages in coral development 

 can be observed in other gentes not closely related to Caninia 

 cylindrica. In fact, the four stages of development : — 



(1) Septa without vesicles ; 



(2) Endophylloid stage — large peripheral vesicles, septa not prolonged 



outwards ; 



(3) ' cylindrica ' stage — septa produced outwards for a short distance only, 



large peripheral vesicles ; 



(4) Septa produced to wall ; 



are well exhibited in the Carcinojphyllum-Lonsdalia progression: — 



Stages 



(1&2) Zaphrentoid Carcinophyllum — major and minor septa thickened at 

 wall so as to be in contact, large peripheral vesicles present only at 

 certain levels. C. mendipense from C-S. 



Stage 

 (2) Carcinophyllum typical — major and minor septa projecting from a 

 thickened inner wall, peripheral vesicles always present, septa not 

 produced outwards. Carcinophyllum 6 from S 2 and D x . 

 (Compare Pi. XXXI, fig. 5— a specimen from the lower part of S 2 .) 

 Stage 

 (3; ' Lonsdalia cf. floriformis' types — inner wall formed of fine crowded 

 vesicles, septa prolonged outwards for a short distance, forming a 

 narrow 'external' area ; large peripheral area. 



Lonsdalia floriformis from D 2 . 



We may also note that Carcinophyllum is essentially a simple 

 coral (I have only seen two compound specimens in a long experi- 

 ence), whereas Lonsdalia is essentially compound, illustrating 

 the general law that compound forms are preceded by 

 simple ancestors. 2 



Endophyllum Ed. & H., Freeh. 



Zeitschr. Deutsch. Geol. Gesellsch. vol. xxxvii (1885) p. 76. 



Exdophylloi bttrrixgtoxexse, sp. nov. (PI. XXX, figs. 4a-4c.) 



* Irregularly -bent, vermiform coral with strong annularthickenings. 



The major septa are thickened only at the wall and do not 



reach the centre, but leave a clear central area occupied by tabulae 



1 Zeitschr. Deutsch. Geol. Gesellsch. vol. xxxvii (1885) p. 76, pi. vii, fig. 2 

 & pi. x, figs. 2, 2a-c. . 



2 See Eep. Brit. Assoc. 1909 (Winnipeg) p. 191. 



Q.J.G.S. No. 267. 2d 



