126 SIPHOPHYCE.E. 



Plate XLV111., Jigs. 6-7. Oogonia and antheridia of V. geminata X 

 200. Fig. 8, non-sexual spores of the same X 200, after Walz. Fig. 9, 

 mature oospore x 200. 



Plate [XL2X., fig. 4, fruiting branch of the variety racemosa, after 

 Hassall. 



7. Vaucheria hamata. (Vauch.) Walz. p. 148, t. xn./. 12-17. 



Aquatic or terrestrial, tliallus rather ri^id, vaguely branched. 

 Oogonia usually single, ovate or ovate-hemisphaerical, seated 

 on a short segment of the divided stem, the other segment 

 elongated, curved, forming the antheridium. Mature oospores 

 involved in a sporoderm formed of four or more strata. 



Cleve Vauch. p. 6. Hassall Alg. t. v., f. 1. Gray AIT. i., 

 289. 



Ectosperma hamata, Vauch. Conf. 26, t. 2, f. 2. Hass. 

 Ann. Nat. Hist. xi.,p. 439. 



Vancheria hamulata, Kutz. Tab. Phyc. vi., t. 61, f. 2. 



In ditches. 



'Vaucher wrote of this species " It differs from all others by the 

 manner in which it carries its grains. The peduncles which sustain them 

 are much elongated, and they bear at their extremity two little threads, 

 the one is recurved and receives the anther, the other is shorter and 

 straighter, and carries the grain.'' 



Plate XLVIII.,figs. 10, 11. Oogonia and antheridia of F. hamata X 

 200. Figs. 12, 13, mature oospores free from oogonia X 200. Fig. 14, 

 sporangium X 200. 



8. Vaucheria terrestris. Lyngb. Hydro. Dan. p. 77, t. 21, f. A. 



Densely interwoven in a thin bright emerald stratum. 

 Oogonia usually single, pedunculate, attached by the flattened 

 base at the back of the incumbent elongated curved antheri- 

 dium. Mature oospores enclosed in a hyaline colourless sporo- 

 derm composed of four strata, considerably inflated. 



Eng. Flora v., 320. Grev. Alg. Britt. p. 191. Eng. Bot. 

 ii., p. 124. Jenner Tunb. Wells, 176. Harv. Man. 148. 

 Johnst. Fl. Berw. ii., 251. Mack. Hib. 234. Gray AIT. i., 

 290. Hass. Alg. 53, t. 5, f. 2. Berk. Glean, t. 9. Walz. 

 Jahrb. p. 149, t. xiii., f. 18, 19. Babh. Alg. Eur. p. 270. 

 Cleve Vauch. 131, f. 1. 



Ectosperma terrestris, Vauch. p. 27, t. 2, f. 3. 



Vauclieria circinata, Kutz. Tab. vi., t. 60, fig. 2. 



Forming patches on damp and clayey soil. 



" Threads more straight and rigid than in V. Dilln-yni, forming a more 

 lax and less interwoven stratum, the summits of the little branches often 

 erect, and giving the whole a bristly appearance." Greville. 



Plate XLlX.figs. 1, 2. Oogonium and antheridium of V. terrestris X 

 200. Fig. 3, mature oospore of same, after Walz x 230. 



Plate XLIX.,fig. 7. Oogonium of V.veliitina, Ag. (a marine species), 

 after Harvey X 200. 



