410 



layer more strongly so llian tlie rest. (Fig. 49). The l)iin(lles 

 were IouikI to he siirroiinded by a sheath containing chlorophyll; 

 stereom was absent; the jjalisade-layers continued unaltered 

 across them. 



At the leaf-apices an extensive epithema was found, 

 consisting, as in the other species, of shortly branched cells 

 with undulating walls. The water-pores open upon an oblique, 

 upwardly-directed surface upon the leaf-apex (Fig. 49, £, 7^). 



The transverse section of the leaf of the hybrid is figured 

 by Andersson & Hesselman together with that of the leaf of the 

 parents; also in this point the hybrid is intermediate. 



The leaf- stalk of li. Pallasii closely resembles the stem 

 in structure and the transverse section is almost circular in 

 outline. 



Batrachium confervoides Fr. 



Synonyms: B. paucistamineum d. eradicatum (Læst.). R. 

 aquatilis v. eradicata (Læst.l. jB.* paucMam. d. confervoides 

 Tullb. B. paucistam, v. horealis Beurl. 



Lit. Gelert, 1894, p. 28. Norman, 1895, p. 33. Rosenvinge, 

 (III), 1896, p. 240. Krdcse, 1897, p. 385. Ddsén, 1901, p. 29. 

 PoRSiLD, 1902, p. 20G. 



Alcohol material from Greenland (Sophiehavn .5.6.8.1883), 

 Iceland, (Nallanes, 10. 1. I894i. 



This species is like the majority of the species of Ba- 

 trachium a perennial, herbaceous water-plant witli branching 

 stems which creep upon the mud at the bottom of the water 

 and send up to the surface in the spring long, filiform, bran- 

 ching shoots. Batr. confervoides has only finely-divided, stalked 

 leaves, arranged in a ^' .-, spiral; the shoot becomes sympodial 

 when flowering begins. The peduncles are of the same length 

 as the leaves; they bend backwards during fruit-setting. Long, 

 slender, adventitious roots, unbranched in places, arise from 

 the nodes of the erect shoots. 



