220 Dr. H. A. Nicholson and Mr. E. Etlieridge, Jtm., on 



with the larger calices may be looked upon as the variety 

 Goldfussi. Edwards and Haime regarded F. gothlandica as 

 an essentially Silurian species ; and the corresponding Devo- 

 nian form was separated by them under the name of F. Gold- 

 fussi. The latter is stated by its authors to be distinguished 

 from the former by its larger corallites and more closely set 

 mural pores. The size of the tubes (1| line), however, is 

 frequently exceeded by typical Upper Silurian examples of 

 F. gothlandica, notwithstanding their more commonly smaller 

 size. Under any circumstances the size of the corallites 

 merely cannot be regarded as a character of the smallest 

 specific value, while the mural pores exhibit an at least 

 equal variability. Upon the whole, therefore, F. Goldfussi, 

 Edw. & H., cannot be satisfactorily separated from F. goth- 

 landica, except as a mere variety. 



In the specimens here referred to F. gotldandica, var. Gold- 

 fussi, the diameter of the calices, as before stated, is about lg 

 line, in extreme cases reaching as much as 2\ lines. In one 

 example there arc four tabula? in the space of two lines verti- 

 cal, whilst in another specimen the same number are contained 

 in a space a little exceeding this. The examples collected by 

 the late Mr. Daintree appear to be only portions of colonies ; 

 but, notwithstanding this, one of the specimens, a very fine 

 one, measures 9i inches by 4|, forming a more or less elon- 

 gated depressed parallelogram. This form of F. gothlandica 

 corresponds in a striking manner with that met with in the 

 Corniferous Limestone of North America, a careful com- 

 parison having been made with colonies of the latter coral in 

 the cabinet of one of us. 



We now come to four specimens, and possibly a fifth, which 

 we look upon as referable to Favosites gothlandica proper, 

 as understood by Messrs. Edwards and Haime. They also 

 bear a close resemblance to F. epidermata, Rominger, from 

 the Corniferous Limestone of North America, which is pro- 

 bably, after all, only another variety of the widely spread and 

 typical F. gothlandica. In the colonies in question the calices 

 are much smaller, scarcely ever exceeding 1 line in diameter, 

 and frequently less, whilst four tabula? appear, on an average, 

 to be comprised within the space of 1^ line vertical. We say 

 on an average, because we find, on the examination of a suffi- 

 ciently large number of specimens gathered from various 

 quarters, and including those from Australia, that there is 

 every gradation between these two conditions in the size of 

 the corallites and disposition of the tabulae. It is on these 

 grounds, combined with the variable disposition of the mural 

 pores, that we propose to consider F. gothlandica in the wide 



