I30 



Ed. and H. probably is merely another form with stalk still 

 intact, but I have no specimen directly comparable. Septal 

 cycles I. and II. are described as equal, the calicle being 2^ 

 mm. long by 16 mm. broad. One specimen of No. 3 similarly 

 has only 12 septa fusing in the axial fossa, its calicle being 

 15 by 1 2 '5 mm. 



In the table of measurements, given above, it may be 

 observed that Nos. i, 2 and 3 differ from the rest far more 

 than the latter do from one another. The corallites obtained 

 in these dredgings were overgrown outside by Polyzoa, weed 

 and barnacles right up to the edge of the calicle, while on 

 the rest isolated serpulid tubes or small masses of Polytrcma 

 alone were found. In addition to differences in size* the 

 corallum is denser and thickert ; the calicles are more 

 rounded at their ends, and there is a tendency to torm spines 

 rather than wings. Indeed the appearances are such as to 

 point to these forms constituting a distinct local race or even 

 ^ variety. Against this view most of these specimens show 

 7 to 9 accretion lines, while in Nos. 4 and 5 these number 

 only 4 to 5. J These bands are so regular in different 

 specimens that it is quite clear that they indicate periods of 

 growth. These periods must be annual, as there are no 

 changes in currents or other oceanic conditions in the region 

 except such. Hence it is possible that the differences are due 

 only to age, the polyps having started on different years, 

 when the conditions were not quite the same. Again the 

 conditions of the various habitats may have differed, and 

 partially caused the variation. Only one specimen of these 

 three dredgings has a young form attached to it. This 

 "has 12 septa, and differs in no respect from those of otlier 

 ■dredgings. 



The group placed by Ed. and H, under § AA and Fl-'F, 

 called by Semper F. variahile, appears to be connected with 

 F. rnbricni by individuals. Some of JSemper's figures have 

 wings and others spines. The scars of all are larger than in 

 the same author's figures of F. ruhnim (= irregnlare). This 

 is probably due to the corallites breaking off in different 

 accretion bands. In the present collection five specimens are 

 doubtful. Most specimens from the Maldives in my posses- 



*The corallites of Nos. 7 and 9 are also markedly larger than those of Nos. 3, 4 

 and 8, 



t This is perhaps due to the stimulation of the incrusting organisms. In one 

 corallitc there is a distinct ring where the latter began to overgrow the caliche, when 

 a fresh growing period seems to have set in, allowing the polyp to resume its sway. 

 In some corallites the epitheca has been broken, and healed or rebuilt. In these the 

 new epitheca is generally thicker than the old, 



i The severance of the corallitc usually takes place in the thinner basal part of one 

 of these bands, a series of punctures being fonne<l round the corallitc. 



