104 



ON THE FOSSIL CORALS OP THE 



It may be that F. Gothlandica is capable of subdivision into the 

 above and perhaps many more species. I think it highly probable 

 that species may be so closely allied that the boundary lines between 

 them are not perceptible to our senses, and in such cases, although 

 we may strongly suspect that they are distinct, yet it is not philo- 

 sophical to proceed by giving them names before we have observed 

 the natural limits by which they are separated. 



In conclusion, therefore, I would propose to refer all the above 

 mentioned species back to F. Gothlandica, there to remain until they 

 are shewn by good persistent characters, actually observed and pointed 

 out to be different. The description of the species should perhaps 

 be as foUows : 



Description. — CoraUum forming spheroidal, pyriform, or large 

 hemispheric or flattened masses ; corallitea in general between one 

 line and one and a half lines wide, sometimes less or more, often two 

 lines ; transverse diaphragms usually complete, rarely incomplete ; 

 mural pores in one, two or three series, usually two, those of the same 

 series about half a line distant, sometimes less i pores surrounded by 

 an elevated margin; faces of tubes with one or two longitudinal 

 strige, more or less distinctly developed ; radiating septa represented 

 by series of small spines, often in the rudimentary form of tubercles. 



In general, the condition in which the specimens have been fos- 

 silized is such that the pores, the border round the pores, the longi- 

 tudinal lines and septal spines have disappeared. Even in well 

 preserved specimens these characters wUl often be absent jfrom par- 

 ticular portions. The following figures are taken from a specimen 

 in the cabinet of the Canadian Institute. 



Fig. 4. 



Fig. 2. 



Fig. 3. 



Eig. 2 exhibits several tubes, some of whieh have complete diaph- 

 ragms, and others incomplete.. In figute 3 the ends of the tubesof 



