168 M. O. A. L. MORCh's REVIEW OF THE VERMETID.E. [Apiil 9. 



Hab. Lord Hood's Island (coll. Cuming.) ; a specimen twisted 

 among the branches of a dead Heteropora, agreeing very well with 

 Wood's figure, which distinctly shows close to the mouth one of the 

 characteristic abrupt feebly excavated varices. The operculum of 

 Fermetus gigantens from Guam, represented by Quoy and Gaimard, 

 pi. 67. f. 14, differs in having an impressed line close to the peri- 

 phery, and in having the muscular impression concentrically furrowed 

 with' lines of alternately different sizes. The operculum in Chenu's 

 ' Illustrations ' has a central red spot, which I have not observed in 

 any of the present specimens. This shell shows a tendency to grow 

 vertically, and unites thus the form described by Junghuhn with the 

 other varieties, which are all creeping. 



Var. S. OPERCULO megacentro. 



Operculum, inferne convexum {nee elevato-converum), limbo con- 

 vexiusculo prominulo angusto ; impressio muscularis magna, sub- 

 tiliter concentrice striata. 



Diam. \7\ m., lat. limbi 4 m., alt. operc. 5 m. 



Hab. Lord Hood's Island (without shell). 



This lid is flatter than that of the preceding, and, although the 

 diameter is only a little smaller, the central area is notably larger, 

 and the brim consequently narrower ; the exterior yellow peripherical 

 band is marked by an elevated margin as if scratched thin. The 

 concentric hues of the muscular impression are more feeble, sharper, 

 and more regular towards the periphery ; they are more distinct, 

 and form small elongate areas. 



Var e. btangularis. 



Earang surumhung, var., Junghuhn, Java, f. 3 (optime). 



T. repens, corrodetis, semiimmeisa, aperturam versus lente crescens, 

 utrinque obtuse angulata, lateribusplanatis, superne planiuscula 

 velleviter concava varicibus arcuatis prcecipitibus ; strics incre- 

 menti membranacece, plerumque ferruginecB ; aperture circularis 

 {pel in specimine incompleto utrinque dilatata ex angulis). 

 Color anfr. primi ferrugineus. 



Spec, majoris long, cavitatis int. 120 m. ; diam. ap. 15 m., alt. 

 14 m. 



Spec, minoris long, cavitatis int. 90 m. ; diam. ap. 15-16 m., 

 alt. 13 m. 



Operculum tenue, convexum, pallide castaneum, superne plano- 

 concavum, laminis appressis concentricis obsoletissimis, utifari- 

 nosum ; area centrali magna, obscura perij)heria elevata; limbo 

 obsoletissime radiato, jjeripheria pallide fiava ; inferne piano- 

 convexum; impressio muscularis opaca, concentrice ruguloso- 

 striata, Iceviuscula ; limbus 7iitidus, castaneus, litiea obscura in- 

 terna terminatus, periphericB margine aiigustissimo piallido. 



Diam. 15 m., hmbi lat. 3-3^ m., alt. circ. 2\ m. 



The upper side is covered with a farina ^eous layer, which, seen 

 under the microscope, seems to show some bodies of the same 



