THE FRESH-WATER ALG.t OF ESSEX. 171 



Tetraspora bullosa, Ag. Cooke, t. 6, f. i. lii i)ools, 

 "Messing (E.G. v.). 



T. lubrica, Roth. Cooke, t. 6, f. 3. In ditches, Kelvedon ; 

 Rivenhall (E.G.V.). 



T. gelatinosa, \'auch. Cooke, t. 6, f. 2. In ditches, Kelve- 

 don (E.G. v.). 



Apiocystis brauniana, Nag. Cooke, t. 7, f. 1. In ditches, 

 etc., Snaresbrook. 



Rhaphidium falcatum, Corda. Cooke, t. 8, f. 4. In pools, 



Snaresbrook. 



FROTOCOCCACE.-E. 



Protococcus viridis, Ag. Cooke, t. 12, f. 1. On trunks, 

 etc., Epping. 



Chlorococcum gigas, Green. Cooke, t. 12, f. 3. In pools, 

 Walthamstow. 



Scenedesmus obtusus, Mey. Cooke, t. 13, f. 5. In boggy 

 pools, Snaresbrook. 



S. acutus, Mey. Kelvedon (E.G.V.). Var. obliijiius. Cooke, 

 t. 13, f. 6c. In pools, Snaresbrook. 



S. quadricauda, Breb. Cooke, t. 13, f. 8. In standing water, 

 Snaresbrook. 



Hydrodictyon utriculatum, Roth. Cooke, t. 14, f. i. In 

 clear water, Kelvedon (E.G.V.). 



Pediastrum boryanum, Turp. Cooke, t. 16, f. 11. In 

 pools, Loughton (Q.M.C.). 



P. rotula, Ehr. Cooke, t. 18, f. 2. In pools, Snaresbrook. 



Hydrianum heteromorphum, Rein. Cooke, t. ly, f. 6. 

 Attached to Algie, Snaresbrook. 



VOLVOCINE.K. 



Chlamydococcus nivalis, Br. Cooke, t. 21, f. 2. On 

 snow. Forest Hill ("Daily News," Mar. 14, 1876) [? Essex.— Ed.] 



' Volvox globator, Linn. Cooke, t. 22, 23. In ponds, 

 Epping ; Loughton : Snaresbrook. 



V. minor, Stein. Cooke, t. 25. In ponds, Eppmg (Q.M.C.). 



Gonium pectorale, Mull. Cooke, t. 27, f. i. In pools, 

 Loughton ; Snaresbrook. 



Eudorina elegans, Ehr. Cooke, t. 26. In ditches, Abridge. 

 DESMIDIE.E. 



Sphaerozosma secedens, D. By. Cooke, Desm., t. 2, f. 3. 

 In pools, Snaresbrook. 



