572 



30. Bulla Cecillii (pi. cxx. f. 22), Philippi. 



B. testa ovato-cylindrica, la3vi, tenui, epidermide olivacea tccta, 

 longitudinaliter substriata; spira distincta, elevatiuscula, anfrac- 

 tibus quinque, sutura corrugata ; apertura angusta, antice valde 

 dilatata ; columella arcuata, simplici. 



Shell ovately cylindrical, thin, smooth, covered with an oliva- 

 ceous epidermis, longitudinally substriated ; spire distinct, rather 

 elevated, whorls five, suture corrugated; aperture narrow, an- 

 teriorly widely dilated ; columella arched, simple. 



Mexico. Mus. Hcmley. 



31. Bulla Bohneensis (pi. cxx. f. 23), Adams. 



B. testa ovato-cylindrica, tevi, subpellucida, alba, epidermide 

 ferruginea tecta, longitudinaUter striata; spira distincta, plana, 

 anfractibus quatuor, rotundatis, primo mammillato ; apertura an- 

 gusta, antice dilatata; columella longa, semitortuosa ; umbibco 

 nullo. 



A much smaller shell than B. Cecillii. It is narrower, more 

 cylindrical ; the aperture is more produced anteriorly j the colu- 

 mella is longer and straighter, and the spire is more depressed. 

 The mud flats at the mouths of many of the rivers of Borneo are 

 partially covered at low water with this animal; the shell is 

 always covered, when the animal is alive, with a rust-coloured epi- 

 dermis. 



Borneo. Adams. 



Sub-genus Akera. 



32. Bulla soluta (pi. cxxi. f. 40), Chemnitz, Mart. Hist. 

 Conch, x. t. 46. f. 1359-01. Ceylanica, Brug. Enc. Meth. vol. i. 

 p. 376. B. resiliens, Bon. B. flexilis, Brown. 



B. testa subcyHndrica, longitudinaUter striata, cornea, dia- 

 phana ; suturis canabculatis ; labro antice fisso. 



Shell subcylindrical, longitudinally striated, horny, diaphanous; 

 sutures channelled, outer hp anteriorly sinuated as if cut off. 



Zanzibar. T. Thome, Esq. Sandy mud ; Philippines. Cuming. 



33. Bulla bullata (pi. cxxi. f. 41), Akera bullata, Mutter, 

 Zool. Dan. p. 242. Icon. torn. ii. t. 71. f. 1-5. B. fragilis, Lamarck. 

 A. Akera, Gm. B. norvegica, Brug. B. soluta parva, Ch. 



B. testa subovata, pellucida, lsevi, cornea; labro superne soluto; 

 spira truncata. 



