RHIZOCLONIUM 



feature being due to the short, equal branches, and to the curvature of their apioe.. Th 

 ": " !._ W : n - m ? rk ! d .^ *"« **" «* * «"*«.. the curvature ulllv 



18:] 



nlj 



hooked appearance 



terminal cell of the branch and Tmetil i, • ' , .T™'"™ " SU1 " y •*"*« 



>™..r»„„» sometimes being so marled as to give the branoh a 



The two well-known species of this genus generally distributed in temperate climate, are : 



Microth amnion K 



Spec Alg. 1819, p. 3B2; Kite. Tab. Phyco- 



nt,"'!' ]L^tJ! or : B r?:. M e- * »**.p- b:3 5 wm a*. 



Hochm 



p. 191, t. 26, f. 1 ; t. 27, f, 2-4. 



] r<>tiM» 



1899, p. 169, t. 7, f. iy-15; Hazen, Ulotrich. and Chwtoph.' U. 8. 1908, 



8'JK) 



(2) ^^^J^^-^ Babcnb., 1859; Krypt. Fl. ft, h, 1863, ,, 266; Flor. Europ. 



Alg m 1868 p 375; Hazen, Ulotrich. and Cha-toph. U. 8. 1902, p. 1,1, t. 20, 

 f. 2-5; 0. S. West, Treatise Brit. Freshw. Alg. 1004, p. 90 (fig. 



M. vexator Cooke in Grevillea 3882, xi, p. 75; Brit. Freshw. Alg. p. 189. 



M. strictimmum Kabenh. var. vexator (Cooke) Schmidle, Alg. preuss. Hoohmoor », 

 p. 169. 



We showed clearly in the <Alg. S. England,' 1897, p. 475, the error upon which Cookt 

 founded his species M. vexator. We have since examined some of Cooke's original ..pec-inuM, tkul 

 obtaining conclusive proof of the identity of M. vexator with M. strictimmum. 



M. curvatum is distinguished from M. Kut-Jngiamon by its longer branch* and by the curat ui* 

 of their extremities. The entire plant has a different aspect, and the cells are I 

 proportionately very much longer. It differs from M. strictissimum in its shorter branches, in their 

 curved extremities, and in its narrower cells. The branching is also much more open and spreading 



arrowor and 



than in M. 



general aspect of the plant is wholly different 



The chloroplast of M, curvatum more nearly resembles that of M. strictimmum than that cf 



M. Kilt 



ingianum. It is small and rather narrow, and only covers a portion of the oell-wall. v 



All the plants observed were free-floating, but doubtless in its younger stages ii is attached. 

 The adult thallus is quite rotund in character, the main branches arising from a more or leaf 

 central point. Nothing that could be called a main axis could be discerned in any of the plants, 

 and the branches are of much more equal size and length than in the other species of this 



genus 



Order : CLADOPIIORALES. 



Family : CLADOPHORACEiE. 



Genus : ' Rhizoclonium Kiitz. 



11. Rhizoclonium hieroglyphicum Kiitz.; em. Stockm. Algengattung Rhizoclon. 



1890, p. 578. 



B. hieroglyphicum Kiitz. Phyc. gen. 1843, p. 205: Ralwnh. Flor. Kurop. 



Alg. iii, 1868, p. 329. 



Crass, fil. 22-31/*; cellulis diametro usque ad 7-plo longioribus. 



Bab.— Banks and backwaters of the Irrawaddy at Bhamo (No. 21502). In rapidly 

 running water in the mountains east of Kawkareik (No. 24450). 





Ann. Roy. Bot. Gard. Calcutta Vol. VI. 



