DASYCLADEtE. ^^ 



n-xl sept. The wall is very thick and tough, and is evidently seen under the mien, - 

 slett be formed of coneentrie layers, deposited one within another, as .n the ce 1 

 : Xf tl!: CMUerpce. When a transverse section of a ^^^^^;^^J'::2 

 of cell-wall appears as if divided into numerous cells, corresponding in number to tic 

 m ilat ILe irom it ; the apparent septa of these su^os^ cel^ b.ng ^d 

 opposite the insertion of the ramelli. This would suggest a stnicture -^ -^^ /^^^ 

 ent from what I have just described ; namely, that the axial tube was no a single cell 

 but xTibe formed by the lateral cohesion of a number of small, cylindrical, longitudinal 

 Ll s pW in a circle ; a structure not very different from what occurs in Ba^- 

 f «m After re;eated examinations and dissections I am disposed to h^.k th t 

 tra pTa^^^^ n^^ of cell-division in the wall is deceptive, and that what look hke sept, 

 r ; elongations inwards, through the wall, of the bases of tl. rame li. Th in e i- 

 nodes of the axial filament are beset with very closely placed whorls ot hoii.ontal 

 11 each composed of a primary, and 3 or 4 secondary, clavate cells ; the prim<u-y 

 rSih.g from the substance of the wall of the axial tube, :^^J^-I^;2^ 

 f +i,« vnmpllns • the secondary cells springing from its apex, ine piimdy 

 ^^^J^^:i:^X^r.or. r.«a., L ^flated at «.e point F^u.^^^'^ 

 ukel Xce bv he tranrforaation of one of tbe secondary or termmal cells of the 

 ^mdta wl,kh s cbanged into a spherical »f»™.,,».".. fille<Uat hrst «th dense 

 ,:Xgr'en granular matter, snrrounded by a pcUacid n,argn,, and ra.sed on a s^» t 



brown or black, staining the paper to which they adhere. 



Fllis's flexure quoted above, are both characteristic ; and so also is that in bioanes 



Cymopolia, but of Amphiroa fragilissivm. 



PiateXLI a FU, 1. Cymoi'IIOLIA barhata ; the natural size. Fig. 2. Apex of 

 Tlate all a. r <j 1. Transverse section ot a 



a branch, crowned with its pencil of bj.soid fabie.. nj. 



branch from which the calcareous shell has been removed. Fig 4 bmall poition 

 iTam soling a. ;>.mn,mm formed from one of the peripheric ramelli. Fr 5^ 

 JtrV^rion^tudLl section of a bi.nch, ^ show the^^^ ^^^^^ ^^ m 



riiagnifi.ed. 



