- -r"-'^ ■ — "J- ^ V 



K - 



THE GENUS CHLOHOCHYTEIUM. 



13 



V. Chlouochytrium GRANDE, BristoL 



This species, first described in 1917 *, differs from all the others in its 

 apparently entirely free existence, independent even of blue-oreen alga?. 

 Tliero is in the cell a single massive central chlorophist somewhat similar to 

 that in C. paradoxum^ with its surface raised into numerous small rounded 

 lobes, and a large central nucleus. 



The life-history of this alga is almost exactly similar to tluit of C\ Facciolaa\ 

 but it must be regarded as im in<lepend(*nt species on account of the far 

 greater size of its cells, the extrusive and very varied thickening of the 

 zooii'onidant>ium-\val], and the extrusion of the zoooonidia throufxh a laro-e 



a O ^ ^ O CD CD 



vesicle formed by tlie gelatinization of the inner layers of part of tlie 

 zooo"onidangium-\vall. 



VI. Chlorochytriuaj Limnanthemum (D. D. Cunningh.), G. S. West. 



This alga, described by Cunninghaiu t tis Slomaiocltytrlian Limnanlhemum^ 

 produces yellowish raised spots on the upper surface of the leaves of 



Limnantheuium indicitm in India. The young cells are thin-walled and 

 contain a parietal chloroplast filled with granules of starch, and a single 



nucleus. 



By free cell-division the contents of the cell become converted into 

 numerous biciliate zoogonidia, which fuse in pairs to form quadriciliate 

 zygotes which develop into vegetative cells* Those zoogonidia wdiich do not 

 fuse were also observed to develop in exactly the same manner as the 

 zygotes. Cunningham considered that the entry of the endophyte into 

 the host-plant is effected through the stonnita by tlie motile zoogonidia or 

 zygotes, and he definitely states that no germination-tube^ such as that 

 observed in C. Lemnte and in other species^ is ever produced. 



VII. CiiLOROCTiYTPJUM ixcLUsor, K] oilman (1883), 



This species is one of a group of very simlhir forms^ which in my opinion 

 should be regarded merely as variations of a single species ; the other 

 members of the group are Cldorocltytrium derniatocolax^ Reinke (1889) , and 

 6\ Schmitzii^ Eosenvingc (1894). 



C. indusum was described by Kjellman j from material growing in the 

 thallus of Sarcopliyllis arctlca and of S, edulis. The cells are spherical or 

 sub-sj>herical in the vegetative state, but the alga frequently possesses 

 irregular bulgings, due to the j)revention of equal growth by the pressure of 

 the surrounL'ing tissue. The cells are completely imbedded in the nurse- 

 plant; they possess a uniformly thin cell-wall and a thin parietal chromato- 

 phore extending over the whole surface. 



* Bristol, B, M. Annals of Botany, vol. xxxL Jan. 1917. 



- t Cunningham, D. D. Sci, Mem. Med. OfF. Ind., Part III. (1887) pp. 3^-40. 

 :|: Kjellman, F. R * Algte of the Arctic Sea/ p, 31^0, pi. 31. tigs. 8-17 (1883), 



