﻿RISSOA.— Pi-ate VII. 



Species G2. (Mus. Brit.) 



RissOA Deshayesiana. Bis, (Bissoina) testa alba, 

 pijramidatd, cosiis longitudinalibus nodosis et 

 striis sptralibus tenuiter reticulata; anfractibus 

 seijtem, convexiiisculis ; apertura semiovatd, colu- 

 mella hrevi, crassd, labio externa crasso, cremdato. 



De.=!HATEs's Rissoa. Shell white, pyramidal, finely 

 reticulated with longitudinal nodose ribs and 

 spiral striie ; whorls seven, rather convex ; aper- 

 ture semiovate, columella short, thick, outer lip 

 thick, crennlated. 



Reclus. Revue Zoologique. 



nab. ? 



Species Go. (Mus. Brit.) 



RiS.soA DEFORMIS. Bis. (Bissuiiia) testa alba, clongatd, 

 solidiiiseuld, altissimd ; anfractibus novem, iiregti' 

 lariter convolutis, inrnqiialiter convexis, superioribiM 

 sculpiis, inferioribus Icevigatis, apertura sub- 

 trigond, prodiictd ; labia externa crassa. 



The defoemed Rissoa. Shell white, long, rather 

 solid, much elevated; whorls nine, in-egularly 

 wound, nneqnally curved, upper sculptured, 

 lower smooth, aperture subtrigonal, produced ; 

 outer lip thick. 



SowERBT. Genera of Sheila. 



Hab. Philippines. 



Species 64. (Fig. a, b, c, d, Mus. Brit.) 



Rissoa vaeiegata. Bis. (Bissoina) testa subcylindricd, 

 alba, vel maculis velfasciis varie pictd; anfracti- 

 bus recti iisculis, superiie ad suturam crenulatis, 

 ultimo majiisculo, apice acuminata, aperturd semi- 

 ovatd, columelhi brevi, acuminatd. 



The variegated Rissoa. Shell rather cylindrical, 

 white, or variously painted with spots or bands ; 

 whorls rather straight, crenulated above at the 

 suture, last rather large; apex acuminated, 

 aperture semiovate, columella short, acuminated. 



Angus. Proc. Zool. Soc. 1867, p. 113. 



Mab. Port Jackson. 



Species 65. (Mus. Brit.) 



Rissoa striolata. Bis. (Bissoina) testa elevatd, tenui, 

 tenuiter striatil, albd, aince acuminata; anfracti- 

 bus „.,rrm, rrrliHScNlis, ,„c,h\nns /k/Zv, .vperiorlbus 

 altrninitis; iilln.in sii h,, ,i,j ii ^t ,ilo : ,i /n rt ii r.! ,inr',- 

 fun,,:. chniiMd iiijr,) ac nn.nif.l : lahin ,,i,_rin. 

 subi'Hcrassato. 



The fine-striated Rissoa. Shell raised, thin, finely 

 striated, white, apex acuminated ; whorls nine, 

 rather straight, middle broad, upper attenuated, 

 last rather narrow ; aperture ear-shaped, colu- 

 mella acuminated below ; outer lip rather 

 thickened. 



A. Adams. Proc. Zool. Soc. 18-51, p. 206. 



Hab. Baclayon, Isl. Bohol, Philippines. 



In some degree resembling Bissoina spirata, but 



the whorls not angular. 



