GENERAL HISTORY. 19 



Dybowski's figures of forms said to possess " Wandstrange," 

 I have no doubt that the bodies thus named constitute an 

 aborted series of " spiniform corahites," such as can be ob- 

 served to occur in various MonticuHporoids. Dr Dybowski 

 lays considerable stress upon the presence or absence of 

 " Wandstrange ; " but, with the views that I hold as to 

 their nature, they cannot be regarded as possessing any 

 classificatory value. 



With regard to the other terms employed by Dybowski, it 

 is only necessary to remark that, in accordance with the views 

 generally held at the time, he regards the " interstitial tubes " 

 of so many of the MonticuHporoids as being of a ccenenchymal 

 nature. W^henever, therefore, he speaks of the absence or 

 presence of "Coenenchym" in any given species, he is to be 

 understood as meaninof that " interstitial corallites " are absent 

 or present. Mr Moseley's researches on HeliopoTa and Mille- 

 pora have rendered it almost certain that the interstitial tubes 

 of the MonticuHporoids are of the nature of a peculiar group 

 of modified corallites, and we can therefore no longer with 

 propriety speak of them as " coenenchymal." 



With regard to the classification of the MonticuHporoids, 

 Dr Dybowski gives the following synoptical table of the 

 divisions of the group which he proposes to adopt : — 



(I.) The corallum consists of tubular corallites. 



A. The walls of the corallites relatively thin and structureless. 



(i.) No " coenenchyma " {i.e.., interstitial tubes); the corallites in 

 direct contact with one another. 

 («) Tabulae present ; the corallites of comparatively considerable 

 diameter. 



1. Genus Dianiilites, Eichwald. 

 (/') Tabulae wanting ; corallites capillary. 



2. Genus Soknopora, Dyb. 



(2.) "Coenenchyma" (/.<?., interstitial corallites) present. 



{a) The individual corallites are surrounded by "coenenchyma." 

 {a) Calices not exsert ; " coenenchyma " vesicular ; corallites 

 of inconsiderable diameter. 



3. Genus Callopora, Hall. 



{a") Calices exsert ; "coenenchyma" of polygonal tubes; 

 diameter of the corallites relatively considerable. 



4. Genus Trac/iyfora, E. and H. 



