40 ART. 12. K. YENDO. 



J. verrucosa Lamx. Histoir. p. 269. t. 9. fig. 4. «. ß. 



= Cor. verrucosa Kütz. Tab. Phyc. VIII. p. 38. Tab. 80. fig. 3. 

 J. parvula Zanard. Coral p. 21. 

 J. gibbosa Lamx. Histoir. p. 269. 



J. compressa Lamx. Freyc. Voy. p. 624. t. 90. fig. 8-10. 

 Cor. constricta Kütz. Tab. Phyc. VIII. p. 40. Taf. 84. fig. 2. 

 Cor. tridens Kütz. Tab. Phyc. VIII. p. 41. Taf. 85. fig. 3. 



This genus is sharply distinguished from the others by the 

 great delicacy of its fronds and the regular ramification. The 

 greatest number of the species ramify dichotomously in a plane. 

 J. decussato-dichotoma branches in an aberrant manner as was 

 described in my former paper.^^ And it is highly probable that 

 this species has been hitherto reckoned among J. adhcerens Lamx. 

 There are many species closely related to J. adhcerens Lamx., 

 found in the warmer parts of the Atlantic and the Pacific Ocean, 

 such as J. capiUacea, J. micrarthrodia f. antennina, J. micrarthro- 

 dia f. tennissima, J. tenella, J. novœ- Zelandce and J. ungulata. 

 The essential distinguishing character lies in the relative size 

 of the articuli. It is a question whether or not it is worthy to 

 serve as a specific character. /. adhœrens Lamx. seems to undergo 

 some change in the minor character. This species stands in the 

 present genus in the same relation as Corallina officinalis L. in the 

 Officinales. 



The articuli are, in the majority of the genus, cylindrical, a 

 few only have compressed ancipitous, and some, slightly com- 

 planated articuli. The pinnate ramules, as has been already 

 remarked, are frequently found at the basal and middle portions of 

 J. rubens var. corniculata and J. micrathrodia f. antennina. At 

 the base of certain species a sort of a delicate ramulet is found in a 

 form of the rhizoidal processes. These ramulets are proliferated 



1) Study of Genicula. p. 8. 



