424 DIATOMACE.E. 



entangled. Frustules short, triangular, ivith two con- 

 spicuous puncta at the end. Lateral surfaces obovate or 

 sub-clavate. 



/3 Frustules scattered, more firmly attached to the stipes, 

 which is more evident. 



Grev. in Hook. Br. Fl. vol. ii. p. 409. ; Harv. Br. Alg. 

 p. 207. Gomph.? olwaceafthr., Die Infus. 218. t. 18. 

 f. 9. ; Pritch. Infus. p. 228. Exilaria minutissima 

 Berk., Br. Alg. p. 22. t. 7. f. 1. Miridion vernale Ag., 

 Consp. Diatom, p. 556. f. 31. Gomph. geminatum 

 Kiitz., Alg. Aq. dulc. No. 13. Gomph. Leiblini Kiitz., 

 Synop. Diatom, p. 568. fig. 46. 



Hob. On stones, &c., in freshwater spring, King's Cliff, 

 Northamptonshire : Rev. M. J. Berkeley. Henfield, Sus- 

 sex : Mr. Borrer. Mayfield, Sussex : Mr. Jenner. Yar- 

 mouth : Mr. Dawson Turner. River Severn, near 

 Shrewsbury : Mr. Leighton. Cheshunt, Herts, and River 

 Lea : A. H. H. At the base of Bandon Mountains : 

 Mr. Andrews. /3. Duddingston Loch : Dr. Greville. 



The stipes in the species in its ordinary state, owing to its 

 being imbedded in a mucous matrix, is often with difficulty 

 discernible. The frustules approach rather closely to those 

 of Gomph. dichotomum; than which, however, they are shorter, 

 broader, and more decidedly cuneate. 



7. GOMPHONEMA MINUTISSIMUM Ag. 



Plate C. Fig. 3. 



Char. Frustules curved, striated; terminal puncta well 

 marked. Lateral surfaces clavate, striated. 



Kiitz. Syn. Diatom, p. 567. fig. 43. ; Ehr. Die Infus. 

 p. 219. t. 18. fig. 5.; Pritch. Infus. p. 228. Gomph. 

 curvatum Kiitz., Syn. Diatom, p. 567. f. 51. ; Kiitz. 

 Aq. dulc. No. 76. 



Hob. Shrewsbury : Mr. Leighton. Shoreharn, Kent : 



