320 



ZOANTHARIA. 



Tubipora. To the present writer the evidence in favour of the 

 view that the Syringoporidce constitute a peculiar group of the 

 Madreporaria Perforata, and that they are nearly related to the 

 Favositidce, appears to be exceedingly strong, and may be briefly 

 summed up as follows : — 



a. The hollow connecting-processes of Syringopora are morpho- 

 logically nothing more than mural pores as existing between coral- 

 lites which are not in actual contact, and, like mural pores, they place 

 the visceral chambers of contiguous tubes in direct communication. 



b. In many members of the Syringoporidce the corallites do 



MM 



Fig. 204. — Syringopora retifonnis. 

 Silurian. 



Fig. 205. — Syringopora verticillata*. 

 Silurian. 



Fig. 206. — Syringopora Dalmani. 

 Silurian. 



Fig. 207. 



-Syringopora compacta. 

 Silurian. 



partially come into direct contact, and wherever this occurs, mural 

 pores of the ordinary Favositoid type are developed. 



c. The septa have the form of vertical rows of calcareous spines,, 

 as is also the case in the typical members of the Favositidce. 



d. The Favositoid genera Syringolites and Roemeria possess the 

 infundibuliform tabulae of Syringopora in combination with the 

 contiguous corallites and serially disposed mural pores of Favosiies 

 and Pachypora. 



e. On the other hand, the Syringoporoid genera Ca?inapora, 

 Cho?iostegites, Thecostegites, and Syringophyllum have the general 

 characters of Syringopora as regards the form of the corallum and 

 the mode of increase, but resemble different members of the Favo- 

 sitidce in the characters of the tabulae, and, occasionally, in the 

 possession of " mural pores." 



