latter form a new asexual generation (compare the germination of the oospore of _Œdogonium_ and _Coleochæte_). The gonimoblasts may arise in three ways:-- 1. In the _Nemalionales_, branched filaments grow out from the oosphere and form an upright, compressed or expanded tuft of spore-forming filaments. 2. In the _Cryptonemiales_, several branched or unbranched filaments (_ooblastema-filaments_) grow out from the oosphere, and conjugate in various ways with the auxiliary cells. The gonimoblasts are then formed from the single cells produced by the conjugation. 3. In the _Gigartinales_ and _Rhodymeniales_ the oosphere conjugates with an auxiliary cell by means of a short ooblastema-filament, and from this auxiliary cell a gonimoblast is produced. The motionless _carpospores_, which sometimes in the early stages are naked, and afterwards invested with a cell-wall, are developed from the terminal cells (and perhaps also from some of the other cells) of the branches of the gonimoblast. The gonimoblasts constitute sharply defined parts of the plant in which the carpospores arise. These parts are called _cystocarps_ and are either naked (Fig. 77 _E_), or surrounded by a covering (pericarp or involucre, Fig. 77 _A_) formed in different ways. On this account the Florideæ were formerly divided into GYMNOSPOREÆ (_Batrachospermum_, _Nemalion_, _Ceramium_, etc.) and ANGIOSPOREÆ (_Farcellaria_, _Lejolisia_, _Delesseria_, _Melobesia_, etc.). The Florideæ are divided into four sub-families:-- Sub-Family 1. =Nemalionales.= The fertilised oosphere produces directly the gonimoblast. Order 1. =Lemaneaceæ.= Algæ of brownish colour and living in fresh water. They lack tetraspores, and the very sparingly branched fertile filaments, composed of many rows of cells, grow out from a proembryo, which consists of a single row of cells bearing branches. _Lemanea fluviatilis_, often found on rocks and stones in quickly flowing streams.