OiP Trondhjem Fiord. 121 



base, when cov(mc(1, have arisen huiulrcds of free strap-formerl 

 branches, usually sinij)le, very rarely dichotomously divided. 

 Tlie uniform strap-shape of tlie branches and their nearly 

 uniform breadth of three to five zocecia, and length of about 

 lialf an inch, give to this Pj)ccinicn a very marked character. 

 The zooccia are always quincuncially arranged, and have six 

 strong lateral spines, the basal spine as a long seta. Height 

 5 inches. Picked up on the sands at Cap Breton, S.W. 

 France, in 1880 (.1. J/. .V.). 



Var. 8. cellariiformis (PI. VII. fig. 6). — A most elegant 

 form. A little bush with erect, round branches ; the un- 

 divided branches are from i to Ij inch long, but seldom more 

 than half a millimetre in diameter; built up generally of four 

 rows of zocecia, which are rather more elongated than usual, 

 with 4 or 6 lateral spines, and the basal spine slender but not 

 setiform. Height 2 inches. Floro Bay, Norway (J.. .17. A^.). 



Var. 9. gemeUariifornus (PI. VII. fig. 7). — Here we meet 

 with E. pilosa performing a most extraordinary gymnastic 

 feat. Two zocecia stand back to back, shoulder to shoulder ; 

 on them mount two similar zocecia, and so the main stem is 

 built up of pairs of cells ; then from both right and left 

 shoulder of every cell stands out at nearly a right angle a cell, 

 which is back to back again with the cell which has been 

 developed from the opposite side of the main stem, and the 

 growth of the branches proceeds as that of the main stem ; 

 and in this way an erect pinnate structure is built up, ultimately 

 becoming bipinnate, and even tripinnate, and the whole com- 

 posed of only a double row of cells. Zocecia and spines as 

 in the last. Floro Bay, Norway, 1882 [A. M. N.). 



Var. 10. eucrateiformis (PI. VII. fig. 8). — This is var. 

 hippothoij'ormis living free, the entire structure being formed 

 ot a single series of cells and pinnately branched. In this 

 case, however, the branches are few and the general appearance 

 is of a mass of long chains lying heaped together. Found 

 with the many other remarkable forms in Floro Bay. 



Vars. 1 to 4 are British forms, the rest are not yet known 

 in our fauna. 



The truly marvellous forms above described exhibit an 

 amount of variation in Electra pilosa^ to which I know no 

 counterpart in the whole range of marine zoology, or, indeed, 

 in any other animal. One extraordinary circumstance at 

 once strikes us. There seems to be common mind at work 



