10 Ain'. ;V- K. YKND«) 



5. Amphiroa zonata, sp. nov. 



l'I. T. fin-. 11 -M : V\. TV. Üg. î). 



Fronde "2~h cm. alta. tcrcti-compressa. latitudine ('(jiiali vol 

 sursum latiore, dichotonia ; raiiiis i-aiimlisque patentibus ; articulis 

 inümi.s l)ievi.s,simis, mediis 0,(S-1.0 miii. latis, 4.0-().() min. longis, 

 supermis compressis linéaribiis, apice latioribiis obtii.sis. pulcberrimis 

 transversi.s striis ; geniculis infërioribu.s diainetriuii iinj uantibus, 

 superioribus poriformibus ; conceptaculis vernicaif<iriiiil)us oblongis. 



The present plant is distinguished fron» otiicrs by having 

 regularly and " indirectly " dichotomous, fiabellate branches. The 

 articuli of the middle and upper portions are compressed Avith round 

 edges, and the terminal articuli have always remarkable transverse 

 striations. In a dried specimen we see a, deep transverse furrow 

 parallel to the apical margin, in the |)lace of the terminal striation. 

 This furrow is of a secondarv importance owing to the contraction of 

 the part in the exsiccation. 



Ill tlie vicinity of the Marine Laboratory at Misaki, we hnd two 

 forms of plants referable to this species. One is always ibund at the 

 littoral region and the other in ô-:20 feet deep water. The former has 

 more patent branches of rosy purple colour, and the terminal articuli 

 are much more compressed : the latter is of greyish purple, with the 

 branches more fastigiate and the terminal articuli less compressed. 

 But the general chjiracters are similar in several respects and sharp 



1) In the dichotomous branching of Oorallinae, I distinguish three types, viz :— 

 I. Indirect dichotomy : articulus diverging l^efore it had a geniculum. 

 II. Direct dichotomy : articulus having twi> genicula at the end, from which the 

 successive articuli arise. 



III. Decussate dichotomy : one ordi?r of dicliotouiy in the pLme nt right angles to that 

 of the adjacent order. 



These expressions would bo repeated in tin' present work. 



