A. F. Verrill — Comparisons of Coral Fmmoe. 



173 



Oculina varicosa Lesueur. 



Oculina varicosa Les., Mem. Mus. Paris, vi, p. 291, pi. xvii, fig. 19, 1820. 

 Dana, Zooph. Expl. Exp., p. 67, fig. 28, and p. 394, 1846, type examined. 

 Verrill, Bull. Mus. Comp. Zool., iv, p. 46, 1864. Pourtales, Reef Corals, 

 p. 66, 1877 ; Florida Reefs, pi. i, figs. 1-4 ; pi. ii, figs. 3, 4 ; pi. iii, figs. 8, 

 9, 1880. Quelch, op. cit., p. 48, 1886. 



Plate XXXII. Figures 2, 3, 4. 



Large Ivory Coral. Tree Coral. 



This is much the largest and finest species of Oculina, as well as 

 the most distinct, but it is comparatively rare, and not often found 

 in very shallow water. 



It branches very distantly, in an irregularly arborescent manner, 

 the few branches being usually crooked, rather long, and tapering. 

 The main trunk may be 30 to 50 mm in diameter ; many of the larger 

 branches are 20 to 25 mm in diameter, in large specimens. 



1 .. 



Y.4'ii 



Figure 9. — Orbicella annularis D. 

 Group of calicles, somewhat 

 enlarged, after Sonrel. Both 

 figures from Webster's Inter- 

 national Dictionary. 



Figure 10. — a, Oculina varicosa Les., 

 tips of two branches with polyps 

 expanded, natural size ; b, part of 

 a branch, more enlarged, after 

 Sonrel, in Agassiz, Florida Reefs. 



The coenenchyma is abundant, very solid, white, and nearly 

 smooth in the trunk and larger branches, but it becomes small in 

 amount on the tapering terminal branchlets, especially near the tips. 



The calicles are mostly of rather large size. The corallites on the 

 principal branches are usually mammiform, with large swollen bases, 

 abruptly narrowing to the cylindrical distal portion, often with the 

 summit and calicle somewhat contracted. But they may vary 

 greatly in the amount of swelling of the base, even on the same 

 specimen. In some eases the bases are very large and much swollen, 

 so as to be nearly hemispherical and in contact pi'oximally. In 

 other cases they are much higher than broad, and subcorneal, but 

 these may also be in contact proximally. On the under sides of the 

 branches and in other unfavorable places, the calicles may be only 

 slightly raised, and the. swollen base may be wanting, or even 

 replaced by a slightly sunken area or fosse, surrounded by a raised 

 border, as in O. robusta Pourt. and some of the other species. 



