EPITHEMIA. 297 



3"5 in 1 c.d.m. ; stride with more robust beads, about 12 in 1 c.d.m. Length, 

 2 to 6 c.d.m. 



Fresh water. Common everywhere. 



var. proboscidea Grun. (H.V.H. Atl., pi. 3T, f. io* ; Type No. 

 254), plate 9, fig. 358. 



Rather small, more flexed than the type form, with apices strongly 

 rostrate capitate. 



Fresh and brackish water. Blankenberghe (H.V.H. ), Alle (Del), St. Trond (Van den 

 Born), England (Norman). Scotland (W. Sm.). 



AA. Costae very radiant, beads fine. 



E. MuSCUlus Kutz. ! (Baa, pi. 20, f. 6 ; H.V.H. Atl., pi. 32, f. 14 

 and 15*; in Types Nos. 50 and 105), plate 9. fig. 359. 



Valve very short, almost semi-circular, with dorsal margin strongly arcuate 

 and showing in the middle a small central nodule ; ventral margin with a very 

 slight, if any, curvature ; apices acute, very gently rostrate. Costa? very radiant, 

 variable in number, approximate; stria; finely moniliform, about 15 in 

 1 c.d.m. Girdle face broadly oval, almost round. Length, 4 to 5 c.d.m. 



Marine. Ostend (Grunow), Heyst (Deby), England (W. Sm., Kitton, Norman), Ireland 

 (O'Meara), Holland, Fiance. 



var. constricta W. Sm. (E. conslricta IV. Sm., S.B.D., i., p. 14, pi. 

 30, f. 248*; Type No. 261), plate 9, fig. 360. 



Frustule more or less constricted in the girdle face. 



Marine. Blankenberghe. England (W. Sm., Kitton, Norman), Ireland (O'Meara), 

 France. 



E. gibberula Klltz. (Baa, pi. 30, f. 3* ; in H.V.H. Type No. 46), 

 plate 30, fig. 825. 



Valve much narrower than in the preceding species, semi-lanceolate, very 

 slightly produced up to the apices which are sub-acute ; costae very distant, 3 

 or 4 in 1 c.d.m. ; striae about 16 in 1 c.d.m., very radiant. Girdle face elliptic 

 or elliptic-lanceolate. Length, 4 to 7 c.d.m. 



Marine. Ostend (Grunow). Probably on all our coasts. 



var. producta Grun. (H.V.H. Atl., pi. 32, f. 11-13*), plate 9, fig. 

 361. 



Apices rostrate. Length, 2 to 3 c.d.m. 



Fresh and brackish water. Antwerp, Brussels (Delogne). 



RHOPALODIA OTTO MULLER, 1895. 



Mr. Otto M tiller has dismembered the genus Epit hernia, and at its expense 

 has created the genus Rhopalodia, which he characterises by the presence of a 



