372 THE JOURNAL OF BOTANY 



Sauvageau, were not distinguished with certainty ; it is possible, 

 however, that one or other of these types w r as absent. 



Streblonema effusum Kylin, Algenflora Schwedischen West- 



kiiste, 1907, p. 49, fig. 13. 



In Ceramium rubrum Ag. Cawsand Bay, Cornwall, August, 



1906. New to Britain. 



The British examples agree precisely with the plant described 

 and figured by Kylin, which likewise occurred in Ceramium 

 rubrum. This species is obviously very closely allied to S. in- 

 testinum (Reinsch) Holmes & Batt., the type-specimen of which 

 was redescribed by the writer last year (Journ. Linn. Soc. vol. 

 xxxvii. p. 295). Distinguishing characters are difficult to grasp, 

 but S. effusum appears to differ in the vigorous habit, with abun- 

 dant production of sporangia ; the latter also are more immersed 

 in the host-plant than in S. intestinum. 



Streblonema volubile Thur. in Le Jol. List Alg. Cherb. p. 73 ; 

 Batters, Journ. Bot. vol. xxxiii. 1895, p. 276. 



A species of Streblonema was observed in Dudresnaya coccinea, 

 which, though not determined with certainty, is worthy of notice. 



S. volubile Thur. was first described and figured by Grouan in 

 1851. It possessed the usual type of creeping filaments, the spor- 

 angia were large, ellipsoid, and unilocular ; no other form of repro- 

 ductive organs was observed. The plant has been noted since 

 by various writers, but in no case has a plurilocular sporangium 

 been found in connection with those of the type above referred to. 



In 1895 Batters (/. c.) recorded the plant as British, and drew 

 attention to its presence in Dudresnaya in various specimens pre- 

 served in herbaria. At the same time lie gave an account of a 

 Streblonema found by Buffham in Gloeosiphonia, and which he 

 doubtfully referred to S. volubile Thur. This plant possessed 

 plurilocular sporangia, which were described as varying in shape 

 from roundish or oval to spindle-shaped, and from 20-70 /x in 

 length, and usually 18-21 /x wide in the broadest part. 



The plant referred to in the present note, which also possesses 

 plurilocular sporangia, would appear to be different to that collected 

 by Buffham. The sporangia are very small, 1-2- seriate, and are 

 frequently found in clusters of two or three together. Their aver- 

 age measurement is 30 x 12 /*, but they may be found to vary 

 within the limits of 20-40 x 10-15 //. The cells of the vegetative 

 portion of the plant also are very small, and are more uniform than 

 usual in species of Streblonema ; their measurements rarely exceed 

 20-30 x 10-15 fi. Five to seven chloroplasts are present in each 

 cell. 



Buffham's plant in Gloeosiphonia and the present plant in 

 Dudresnaya are almost certainly distinct. Mr. Batters (the news 

 of whose lamented death has just been received), who was kind 

 enough to examine the latter and to compare it with Buffham's 

 slides in his herbarium, stated that as far as he could see the one 

 would appear to come as near the true S. volubile as the other. 

 Until, however, further information is forthcoming, it is impos- 

 sible to speak definitely. 



