wiih a revision of thè Limnmdce of Authors. 
361 
Fig. 2. — Female reproductive sjstem. b, Genital bladcler. 
a, Uterus. s, auxiliary gland, v, Oviduct. o, Ovaiy. 
Fig. 3. — Male generative System, a, Foramen. b, Penis. 
c, Retraetor muscle. d, Yas deferens. e, Prostate, f, Epidi- 
dyniis. h, Testiele. 
Fig. 4. — FTervous System. 
Fig. 5. — Circulation. h, Heart. 
Fig. 6. — a, Top view of ova capsule of Pomgyholyx solida. 
b, Section of thè same. 
Fig. 7. — a, Shell of Porajyholyx var. solida, b, Side view of 
thè eye. 
Fig. 8. — Teeth of Physa humerosa slightly separated. a, 
Uncinai teeth. b, Plenrals. 
Fig. 9. — Teeth of Pomjoholyx var, solida, a, Rhachidian 
tooth. b, Side view. 1, First pleural. c, Side view, 5, Fifth 
pleural. 8, Eighth pleural. 10, Tenth do. 11, Eleventh do. 
18, Eighteenth lateral or first uncinai.* 
Fig. 10. — z, Rhachidian tooth of Limncea stagnalis. x, ditto 
of Planorbis lentus. o, Rhachidian tooth bf Physa humerosa. 
Fig. 11, — a, Buccal piate of Pompholyx xw. solida, b, ditto 
of Physa acuta (from Moquin Tandon.) 
Fig. 12. — Buccal piate ofLimncea stagnalis Tandon), 
1, 1, Accessory lateral j^lates. 
Fig. 13. — Rhachidian tooth of Acella gracilis, Jay, 
Fig. 14. — Rhachidian tooth of Carinifex Ffewherryi. 
* As comparisons may be instituted between tbis and otber publisbed figures 
of thè dentition of Pompholyx, it may be well to state that some twenty-five 
specimens of thè radula have been critically esamined and compared, and 
their agreement with thè present figure is indubitable. The specimens were 
examined by thè writer, and also by Prof. Theodore Gill of thè Smithsonian In- 
stitution, Mr. W. G. Binney, and Mr. Thomas Bland. 
To Mr. Binney I am under great obligations for his kindness in assisting 
me to obtavn for examination his originai specimens of thè radula of thè 
typical Pompholyx effusa, and for opportunities of looking at his originai pho- 
tographs, taken from thè same by Mr. Samuel Powel. 
