280 BIVALVE SHELLS. 



10. PiSUM LENTICULARE. 



P. testa transversa ovata, compressa, inaequilaterali, antice 

 producta, temii, diapliana, subtilissime striata, albido-rufes- 

 cente ; umbone obtuso ; ligamento inconspiciio. 



Cyclas leuticularis, Normand, Notice sur quelques Cyc/. p. 8. no. 4. 

 f. 7, 8. 

 Hub. In fluvio Scaliliac. 



11. PisuM Creplini. 



P. testa plus minusve ventricosa, orbiculato-rhomlx)idea, vel sub- 

 ovali, inajquilaterali, antice producta, ])ostice brevi, tenui, pel- 

 lucente, concentrice atque tenerrime striata, unicolore lutea 

 seu albo-lutescente, sen zonis cinereo-nigricautibus et luteo- 

 olivaceis picta ; umbonibus obtnsis, plus miuusve tuberculosis, 

 antrorsum inciu-vis, ap])roximatis ; ligamento minimo, fere in- 

 conspicuo, latere breviori insito; dente bitido cardinali in 

 utraque valvula ; laterales duo valde compressi. 



Cyclas Creplini, Dunker, Zeitschr.fur Malac. 1845, p. 20. 



Hab. In fossulis paludosis prope Casselis loco Hottenkirchen 

 dicto. 



2. AfricanoB. 



12. PiSUM PARASITICUM. B.M. 



P. testa ovato-transversa, convexduscula, inaequilaterali, trans- 

 versim tenue et irregulariter striata, epidermide viridi-fusces- 

 oente vestita, atro-rubescente aliquantisper intus extusquc 



{)uncticulata ; latere antico bren, obtuso, angusto ; postico 

 atiore extreinitate obtuse truncato • raargine su])eriore recto, 

 inferiori parallelo ; cardine angustissimo, dentibus cardinalibus 

 obsoletis, lateralibus angustis, brevibus; umbonibus magnis, 

 obtusis, obliquis. 



Pisidium parasiticum, Parreys, MSS. 



Hab. In Nilo superiore. 



13. PiSUM LUMSTENIANUM. B.M. 



P. testa ovata, oblique trigona, tumida, inaequilaterali, transversim 

 striata ; natibus ])romiuentibus, roseo-corneis. 



Pisidium Lumstenianura, Forbes, Moll, of Algeria, Ann. of Nat. 

 Hist. ser. 2. no. 10. 1S38, p. 255. no. 45. pi. 12. f. 4. 



Hab. lu fonticulis Mitidjana;. 



