46 COCCOPHYCE^E. 



Ccelastxum cambricuzn. Archer Micro. Journ., 1868, p. 65. 



Cells rounded on the exterior margin, each bearing a single 

 truncate tubercular process. 



In pools. 



" It was obtained by Mr. Archer on his visit to Wales, and is not re- 

 ferable to either of the remaining forms (besides C. sph(ericui) as 

 described by Nageli, though perhaps showing most affinity with Ctflas- 

 trum cuLicu/n, but differing in each cell possessing but one process, or 

 tubercle-like appendage, not three. These likewise showed various con- 

 ditions of the growth of the younor coenobia within the mother-cells from, 

 the earliest stage, tlie most minute of which showed the full character 

 of the cells, each with the truncate tubercle-like process."- Quart. 

 Journ. Micro. Soc., I.e. 



Coelastrum microsporum. (Nag.) Braun Alg. Unic. p. 70. 



Cells 8-1 6 or 32, exactly spherical, containing a single globule ; 

 interstices small. 



SIZE. Coenobium -04 mm. diam. ; cells '009 mm. diam. 

 Mtcr. Journ., 1868, p. 65. Pritchard's Infus. f, 755. 



In bogs and pools. 



" The group (ccenobium) is formed of rather large cells, externally 

 globularly rounded, their margins, where in mutual contact, being 

 straight, and leaving at the angles exceedingly minute, somewhat tri- 

 angular interspaces, like very minute pores, leading into the central 

 cavity characteristic of the forms appertaining to this genus." Archer. 



GENUS 31. STAUROGENXA. Kutz. 



Ccenobium cubical, hollow within, formed of 4-8-16 quad- 

 rate or sub-quadrate cells. Propagation by quiescent gonidia, 

 produced after the subdivision of the cell-contents. Rab.Alg. 

 Eur. iii. 80. 



Crucigenia, Morren in Ann. des Sci. Nat., 1830, t. 20, p. 

 404. 



Staurogenia rectangularis. Brown Alg. Unic. p. 70. 



Cells oblong-oval, 4-16-64, associated in tabular families, 

 almost twice as long as broad, angles obtusely rounded. 

 SIZE. Cells -0075 x '004 mm. 

 Archer in Quart. Journ. Micr. Sci., 1875, p. 206. 



In pools. 

 Plate XniL fig. 3. a, families X 400 ; 6, magnified 800. 



GENUS 32. SORASTRUM. Kiitz. (1845.) 



Ccenobium globose, solid within, free swimming, formed of 

 4-8-16-32 compressed wedge-shaped cells, which are sinuate, 

 emarginate, or bifid at the apex, and radiately disposed. Pro- 

 pagation unknown. Ralh. Alg. Eur. iii. 81. 



