328 THE ZOOLOGIST. 



I have given Mr. Whiteaves' localities in addition to my own, 

 with the view of making this list more complete. 



AQUATIC MOLLUSC A. 



Order Lamellibranchiata. 

 Fam. I. Sph.erud/E. 



Spluerium corneum, Linn. — Plentiful and generally distributed ; 

 especially abundant in all stagnant waters. 



Var. fiavescens. — Occasionally met with. 



S. rivicola, Leach.— Abundant in the Isis and Cherwell Rivers 

 and their tributary streams ; found sometimes in company with 

 S. corneum. 



S. lacustre, Muller. — I bave not met with this species; but 

 Mr. Whiteaves records it under the specific name " caligidata " as 

 "found abundant in a railway lake at Wolvercot, chiefly at the 

 end which is choked up with a profuse growth of Ceratophyllvm 

 demursum. It occurs also in peaty pools near Headington Wick 

 Copse." This latter locality will, I think, no longer hold good, 

 for the pools have ceased to exist, owing to drainage, but the lake 

 at Wolvercot still seems a likely place. 



S. ovale, Ferussac. — A single specimen dead, but in good con- 

 dition, with the valves united, from the canal near Wolvercot. 



Pisidlum amnicum, Muller. — Abundant; in parts of the Isis 

 and Cherwell, but more especially in their tributary streams. 



P.fontinale, Draparnaud. — Common and generally diffused. 



Var. jndchella. — Not uncommon in gravelly ditches (Whit.). 



Var. Hcnsluainua. — In several places in the River Isis, espe- 

 cially near Rinsey (Whit.). 



P.pwnttum, Gmelin. — Not very plentiful. Mr. Whiteaves took 

 it in a ditch near Watereaton, and I have it from near Marston 

 and near Headington from weedy ditches. 



Var. obtusaliH. — In a stream near Botley (Whit.). 



P. iiilidum Jenyns. — Rare ; in a half-dried ditch near Hincksey 

 Ferry I met with a few specimens, and Mr. Whiteaves took two 

 specimens from a ditch near Summertown communicating with 

 the Cherwell. 



Fam. II. Unionid^e. 



Unio tumidus, Philippsson. — Rather plentiful in the canal, and 

 also taken in the Isis and Cherwell. In 1854, says Mr. Whiteaves, 



