CHROOCOCCACEA. 213 
sion proceeds, orifices are formed in different parts, until the whole 
becomes a Coarsely latticed sac or clumsy net of irregularly lobed form. 
Then this becomes broken up into irregular fragments of all shapes and 
sizes (giving the stratum a granular appearance to the naked eye), each 
of which recommences the expanding growth, and becomes a latticed 
frond. The internal cells are very minute, but have a distinct margin 
with internal granules. They multiply by dividing into two and four. 
The gelatinous frond always presents a transparent border or peripheral 
stratum, destitute of green cells ; but no boundary membrane exists, the 
surface exhibiting a softened or half-dissolved aspect. On the approach of 
winter the fronds ceased to increase, and by degrees most of the gelati- 
nous masses faded to a light brownish tint, swelled up and settled to the 
bottom of. the water in light flocculent clouds. They appear to become 
half-dissolved, and to allow the green cells to become free, as many of the 
latter were found free, adhering to the sides of the vessel. Perhaps these 
reproduce the fronds in the next season. No zoospores were ever de- 
tected.” —Henfrey. 
Clathrocystis raseo-persicina, Cohn., is already included in this work, as 
Pleurococcus roseo-persicinus, pl. 2, fig. 6. 
Plate LXXXVT. fig. 7. uw, Thalli magnified 200 diam. ; b, cells mag- 
nified 400 diam. 
GENUS 86. CELOSPHZERIUM, Wiig. (1849.) 
Thallus globose, small, vesicular, hollow, composed of small 
cells, which are associated in families at the periphery, im- 
mersed in a mucous stratum, formed from the speedily confluent 
teguments. Increase by division of the cells in all directions. 
Celospherium Kutzingianum. dg. Finz. Alg. p. 54, t.1e. 
Families spherical. Cells subglobose, geminate, or quater- 
nate, loosely disposed; cell-contents blue-green, delicately 
granulose. 
Sizz. Cells -002--005 mm.; families -06 mm. and more. 
Rabh. Alg. Eur. ii, 55. Quart. Journ. Micr. Sci: 1869, p. 
197. Kirch. Alg. Schles. 254. , 
In ponds, meres, &c. 
Plate LXXXVIL. fig. 1. Families magnified 400 diam. 
GENUS 87. GOMPHOSPHZERIA. Kutz. (1836.) 
Cells wedge-shaped, peripherical, 2-4-8 associated in radiating 
families nestling in jelly, covered with a tegument, and forming 
a solid globose free-swimming thallus. Cells dividing alter- 
nately in three directions, 
Gomphospheria aponina. Kutz, Tad, 1.,t.31,f. 8 
Thallus microscopical, blue-green, often becoming pale, tegu- 
ment colourless, rather thick and somewhat lamellose, central 
cells smaller, cell-contents verdigris or pale blue-green, 
