532 OILBIiBT 0. BOURNE. 



|)urtio!i oi ;i sccLiuii of this coral is represented in fig. 3J3. Tlu! 

 calicoi)lasts liave the same characters as in Caryoi)hylliaj and 

 where they form a deeper layer the same incoherent vacuolar 

 structure is observable. Fig. 34 represents part of the tissues 

 clothing the upper and inner edge of a septum in this species. 

 The endodcrm cells arc well preserved, but the central mass of 

 calicoblasts Icjok as if they had undergone prolonged maceration. 

 I do not, however, believe that this is the case, but that the 

 loose vacuolar ai)})carancc of the protoplasm — one can hardly 

 speak of cells, for no cell outlines are visible — really re[)rcsenLs 

 the structure of the culicol)last layer, i^'or the same cluiractcrs 

 are present wherever the ealicoblast layer attains any thickness, 

 and the only places where it does attain any thickness are at 

 the edges of the septa, and deep down in the angles between 

 the septa where the edge-zone overlaps the edges of the theca. 

 In all cases the surrounding tissues were very well preserved, 

 and the state of their preservation may be judged from fig. 33. 



in Mr. IJrook's collection were also many sections of 

 Madrepora. 1 am unable to determine the species for the 

 same reasons as stated for Euphyllia. Fowler has spoken (7) 

 of a "distinct" layer of calicoblasts in JNladrepora Dur- 

 villci. The layer is distinct enough in my specimens so far 

 as the [)resencc of nuclei and surrounding cytoplasm goes, but 

 there are no cell outlines, and the cytoplasm is vacuolated and 

 irregular as shown in (ig. 42. 



1 have noticed the same phenomena in several other corals, 

 viz. extreme attenuation of the ealicoblast layer in all but 

 certain well-defined' places, and in those a mass of vacuolar 

 protoplasm of irregular outline with no cell boundaries. These 

 characters, therefore, appear to be normal for a considerable 

 number of corals. 



On the other hand, there are the elongate cells of Mussa, and 

 those described by Fowler (9) in Lophohelia prolifera. 

 To satisfy n)yself as to the latter species J have made a series 

 of [jrcparaLions, but the tissues were too much injured by j)ro- 

 longed action of spirit to allow me to speak with certainty 

 about details, it is sullicient to say that 1 found elongate 



