POLYNESIAN GONIOPOILE 47 



spicuous palif'orm knobs appear. In sections parallel with the surface the individual calicles 

 are easily traceable by the zigzag lamellate walls separating groups of large irregular inter- 

 septal loculi, which appear between some twelve thick, rough, lamellate septa. 



We appear to have here almost an extreme form of the sheaf-formation. We have a very 

 rapidly expanding bundle of thick lamellate septa, which rise up in a most conspicuous 

 manner on the top of the walls. This is interesting because of the tendency to the same 

 growth-form seen in specimen a of the last type. There we could attribute it to great 

 rapidity of growth, but here nothing of the kind is suggested. 



Dr. Ortmann has figured a form which he called " G. parvistella," believing that it had the 

 smallest calicles of any known representative of the genus, which was perhaps true at the 

 time, but is no longer so. But, beyond quoting his figure and noting the superficial likeness in 

 the calicles, which however were much shallower, and that the growth-form was a cluster of 

 irregular knobs which but faintly suggest the same expanding cone formation, little further 

 use can be made of his work. Instead of describing a form, he made a " species " containing 

 specimens from Tonga and from Samoa, and he unfortunately omitted to say to which his 

 figure referred. (See, however, under next heading.) 



The special points in this coral, apart from the sheaf-formation, are the very small calicles, 

 the obscuring of the radial symmetry by the fact that prominent septa often seem to run 

 parallel to one another, the great thickness of the septa, and their conspicuous appearance on 

 the margin of the walls where they are thick, crowded, and laminated. 



a. Zool. Dept. 91. 3. 6. 20 



14. Goniopora Samoa a) l. (PI. I. figs. 8-9 ; PI. XI. fig. 8.) 

 ["Probably No. 1285 of the Godeffroy Collection, ' Goniopora sp., Samoa' " ; British Museum.] 

 ? Goniopora parvistella, Ortmann, Zool. Jahrb. in. (Syst.) (1888) p. 158, pi. vi. fig. 3. 



Description. — Corallum forms towering masses (over 20 cm. high), apparently built up by 

 thick incrustations, the surfaces of which rise into club-shaped masses, with rounded tops and 

 sides often flattened by mutual crowding. Too irregular to be called columnar. The lower 

 edges of the growing tops may join across the valleys, obliterating the column-like growths of 

 former periods. An epitheca appears under the edges of the living layers, but the dead faces 

 are not covered by any pellicle. 



The calicles (PI. I. fig. 8 near the top ; fig. 9 from a detached fragment of the base) are 

 very variable in size, average 3 mm., polygonal, with many double calicles, everywhere shallow. 

 Walls often hardly traceable, usually low, irregular ridges of half-flaky, half-filamentous reti- 

 culum. In the more regular calicles the inner margins of the walls show fine septal points, but 

 there are only faint traces of radial symmetry ; thin curling, irregular septal threads soon join 

 a large columellar tangle of the same open flaky reticulum. Above this tangle the septa can 

 be seen to be fusing, especially in the basal calicles, fig. 9, but even there the typical formula is 

 obscured. The interseptal loculi are very irregular, and hardly distinguishable from the round 

 pores in the reticulum. On the summits, and apparently the most rapidly growing parts, the 



