52 



var. 1. squamulosa Mörch. Proc. p. 158. 



T albescens, planorbiformis vel repens, saepe profunde corrodens, longitudinaliter lirata, 

 lirae approximatae, huc illic alternatim minores, nodulis transversim compressis sat remotis 

 et in locis occultis squamis parvis acutis ornatis; lirae 1 — 2 laterales interdum validiores; 

 Striae incrementi obliquae, obsoletae squamiferae; apertura subcircularis. 



Operculum membranaceura, diaphanum, pallide flavum, superne sat concavum vix 

 striatum, inferne convexum, limbo latissimo planulato, flavo, nuido, liris concentricis tribus; 

 mammilla centrali prominente obtusa, obscure purpuracea, fascia basali aurantia circumdata. 



Diam. l 3 / 4 mm. 



An. Tridacna scapha. Mensch. 



var. 2. cristata Mörch. Proc. 1861 p. 158. 



T. triquetra, crassiuscula, carina mediana, squamis validis remotis; utrinque angulis 

 acutis, squamis latis angulatis ornatis; lirae incrementi pulcherrimae reguläres, arcuatae, 

 leviter flexae in interstitiis; apertura superne rectangularis. 



Diam. 2'/ 2 mm. 



var. 3. subdecussata Mörch. Proc. 1861 p. 158. 



T. repens, profunde immersa, obtuse quadrangularis, antiquata, lirulae longitudinales 

 subtilissimae, interruptae, Striae et lirulae incrementi subtilissime conferte undulatae unde 

 obsolete granulosae. 



Diam. 2 mm. 



Operculum differt a precedentis macula coccinea centrali latiore. 



var. 4. spinosa Mörch. Proc. 1861 p. 159 t. 25 fig. 16. 



T. gracilis, Candida, irregulariter spinosa, squamosa, vix lirulata, intus lacteapolitissima. 



Operculum pallide aurantiacum, superne infundibuliforme, centro impresso, spiraliter 

 conferte lirulato, nodulis microscopicis subcylindricis vertice medio inflexo spiculis obsitis; 

 inferne breve conicum; area muscularis parva, margine concentrico elevato-terminata ; centro 

 acuto submamillato rufo, limbo latissimo, nitito, pallide aurantio, margine angusto, peripherico, 

 pallidissimo terminato. 



Diam. 2 mm. 



13. Siphonium nebulosum Dillwyn. 



Tüyaux de mer Davila Cat. 1767 I p. 100 t. 4 fig. 12. 



— — Favanne I p. 652 t. 6 fig. 3. 



Serpula nebulosa Dillwyn II p. 1076 Nr. 19. 



