198

CYSTOSrERMEJE.

6. Vesiculieera Cuvieri Hass.

Char. Filaments more slender than those of the precedingspecies. Cells usually seven times as long as broad. Spo-rangia oval, contained in inflated cells of an ovate form.

Vesiculifera prolongata Hassall, In Annals of Nat. Hist.,x. 390. Prolifer a Cuvieri Le Clerc, Mem. clu Mus.

Hab. Pond near Louton, Essex, and again near Enfield :A. H. II.

This species is known from V. Landsboroughi by its finerfilaments, longer cells, and ovate form of the seed-bearing in-flated cells.

“ The inflations of Prolifera rivularis present an oval, whosegreat diameter is never double the small. In the ProliferaCuvieri this enlargement is so much allongated that onemight distinguish it almost as well by the intensity of its colouras by its size. In its state of greatest contraction its greatdiameter is triple or quadruple that of the small. The sameproportion, but a little less marked, is observed between thegrains of the two ConfervoeC

7. Vesiculieera lacustris Hass.

Plate LII. Fig 1.

Char. Filanients nearly equal in diameter to those of V.Cuvieri. CoWa from three to Jive times as long as broad.Sporangium oval, sometimes almost quadrangidar, solitary,occasioning no very considerable enlargement of the cellin which it lies ; empty cell next the spore also inflated.

Vesiculifera lacustris Hassall, in Annals of Nat. Hist.,vol. x. p.390.

Hab. In the New Fiver reservoir, near Cheshunt , spar-ingly, and other places in the vicinity : A. II. II.

V. lacustris differs from V. Borissii principally in being al-together a more robust species, and in having shorter cells.