A. JE. Verrill — Comparisons of Coral Fatmce. 191 



According to Mr. R. Rathbun (op. cit., p. 542), it usually does not 

 occur attached to the reefs, but on the mud-flats, in sheltered places, 

 partially buried in the mud, and usually unattached when mature 

 (at Bahia, etc.). But when young it is, even in such places, undoubt- 

 edly attached to small pieces of stone, or shells, as is the case with 

 other similar corals (Mmandra areolata, etc.). 



A young specimen from the Abrolhos Reefs, in the Yale Museum 

 (No. 4537, coll. C. F. Hartt), was, however, firmly attached by a 

 pedicel 23 mm long and 16 mm wide, and somewhat expanded at the edge 

 of the attached base.* 



This specimen (fig. 14, above) is 52 mm long, 33 mm wide, 32 ram high. 

 The valleys are mostly 7 to 9 mm wide ; the collines (and septa) are 

 about 8 to 9 mm across, where simple. 



Thus all the calicinal centers and grooves and their septa are much 

 smaller and narrower than in the adult, which is in accordance with 

 all young meandriform corals. 



Its margins are deeply tabulated, with four lobes on one side and 

 five on the other. The infoldings that form the collines are deep ; 

 three of the collines on each side have already subdivided distally 

 into two or three short lobes, defining short valleys that start out 

 from the median valley, which is as narrow as the lateral ones. 



The septa are rather thin, alternately wider and very narrow, but 

 the wider ones are alternately unequal, as if in three cycles. The 

 larger ones are broadly rounded distally, little exsert, nearly per- 

 pendicular within the valleys. The distal third of their edges is 



* In contrast with this specimen, I add a description of a young example of 

 M. meandrites, of almost exactly the same size, from the Bahamas, collected by 

 R. P. Whitfield, and now in the Amer. Mus. Nat. History. It was firmly 

 attached by the central part of the base. 



Length, 50 mm ; breadth, about 18 mm ; height, about 85 mm . It has six primary 

 marginal folds or lobes, and about three small secondary ones, some just form- 

 ing, and a little irregular. 



The septa are somewhat exsert, entire, or nearly so ; the edge is convexly 

 rounded and narrowed distally. Small narrow ones alternate with the wider 

 ones. Columella large, formed of small convoluted lamellae and trabecule, 

 without any median continuous lamella. Collines narrow, double in most parts. 



External wall with raised, unequal costae, two or three small ones between the 

 larger ones, and sparsely serrulate with small, rough denticles. 



" Color of the animal, in life, emerald green" (Whitfield). 



Another young specimen, from the same collection (No. 507), is a little larger. 

 Length, 75 mm ; breadth, 62 mm ; thickness, 36" im . This is already meandriform, 

 with deep valleys and stouter collines. The columella is small, but coarsely 

 lamellose, with irregular thickenings, but without a median lamella. 



