15 



Bythinia, Prid. 



125 tentaculata, L.— 54. 



b. ventricosa, Menke. 



c. angulata, Roberts. 



d. excavata, Jeff. 



e. albida, Rimmev. 



f. decollata, Jeff. 



g. producta, Menke. 



h. cornea, Loc. 



i. rnfescens, Ckll. 



k. scalariformis, Roberts. 

 1. fulva, Loc. 

 m. zonata, Baudon. 

 n. cinerea, Loc. 



126 leachii, Shepp. — 28. 



b. elongata, Jeff. 



c. albida, Rimmer. 



RISSOID^E. 



Hydrobia, Hart. 



127 similis, ' Drap.' Aactt. -1 

 = confusa, Frauenf. 



b. Candida, Jeff. 



127 2 jenkinsi, E. A. Smith. 

 = ovata, Jeff. 

 b. carinata, Marshall. 



128 ventrosa, Mont. 



b. minor, Jeff. 



c. decollata, ^c/f. 



d. elongata, Jeff. 



e. pellucida, J^/f. 



129 ulvae, Penn. 



b. albida, Jeff. 



c. barleei, y<?$\ 



d. octona, l L.\ Jeff. 



e. tumida, Marsh, ms., 



Somerv. 



f. decollata, Marsh, ms., 



Somerv. 



VALVATID^E. 



Valvata, Mull. 



130 piscinalis, Mull. — 50. 



b. depressa, C. Pfr. 



c. subcylindrica, Jeff. 



d. acuminata, Jeff. 



e. pusilla, Mull. 



f. sinistrorsa, ''Jeff.', T 



g. albina, TVy'. 



131 cristata, J/ ?>://. — -32. 



b. alba, Rowe. 



c. subscalaris, Baud. 



CYRENID^E. 



SPHAiRIUM, Scop. 



132 corneum, L.- — 60. 



b. flavescens, Mc Gill. 



c. nucleus, Stud. 



d. scaldianum, Norm. 



e. pisidioides, Gray. 



f. compressum, Gray. 



g. minor, Gray. 



h. stagnicola, Leach ms. 



Jen. 



i. regulare, Pascal. 

 k. brunneofasciatum, 



133 rivicola, Leach. — 19. 

 b. compressum, Pasc. 



134 ovale, Fer. — 7. 



b. pallidum, Gray. 



