212 



Papers from the Marine Biological Laboratory at Tortugas. 



described by me as Lepralia serrata n. sp., from the Woods Hole region 

 (1912, p. 242, pi. 26, fig. 57). 



After a careful study of the Florida specimens I am of the opinion that 

 this can be only a variety of L. contractu Waters, described from Madeira 

 (1899, p. 11). Waters's description is brief and his figures small, but 

 Norman (1. c, pi. 41 , fig. 56) has refigured the species. The differences seem 

 to be largely in the secondary calcification, which appears to be much greater 

 in American specimens; also there are six oral spines in Madeira specimens, 

 while usually only four are to be observed in American material. The 

 avicularia in Florida specimens are much more abundantly developed and are 

 frequently raised high above the front of the zooecium on small mammillary 

 processes. Also, the lateral oral denticles are much more prominent than 

 they appear in the figures of Madeira specimens and are strongly bifid; 

 however, Norman figures one such bifid denticle. In one of my speci- 

 mens the spatulate avicularia are extremely elongated, fully as long as the 

 zooecium, and, while usually directed forward, are sometimes reversed in 

 position. The zooecial wall appears to be much more thickened than in the 

 Madeira specimens, to judge by the figures of Waters and Norman. Not- 

 withstanding these differences I believe they are closely related. The form 

 of the ooecium with the peculiar membranous area and the serrated char- 

 acter of the primary zooecial orifice are identical and are so unique that I 

 believe them to indicate the same species. Specimens from southern New 

 England are much more highly calcified than Florida specimens, which 

 seem in some respects to be intermediate between those from New England 

 and Madeira. 



Lepralia edax (Busk). 



Busk, 1859, p. 59 (Cellepora edax).—Sum, 1873, p. 63 (L. edax formce typica and 

 ca/carea).— HiNCKS, 1880, p. 311.— Verrill, 1909, p. 54. 



One colony taken at 18 fathoms, forming a cylindrical mass more than 

 0.25 inch in diameter and many layers in thickness, which originally sur- 

 rounded a branched structure of some sort, and one colony taken at 8 

 fathoms incrusting a shell fragment. Smitt's figures and description of 

 this species are very complete. I have compared these specimens with one 

 from the English Channel sent me by Dr. S. F. Harmer. English speci- 

 mens are said to be found only on certain species of gastropod shells. While 

 Florida specimens have not been taken in such situations, I can distinguish 

 no differences of any importance. My Tortugas specimens belong to what 

 Smitt calls the forma calcarea, but it can scarcely be considered a distinct 

 variety. 



The large, pointed, vicarious avicularia described and figured by Smitt 

 are abundantly distributed over the colony. The ovicell has a peculiar 

 membranous area on the upper surface, a feature also possessed by L. 

 contracta Waters, though in the latter species this area is much nearer the 

 zooecial aperture. 



