8o 



Decaisni l ), 1842, based his division of the family oi the Corallinaceae on the form and 

 position of the conceptacles and distinguished the genera: Corallina, Jania, Amphiroa and 

 Melobesia. Under the name oi Amphiroa he united all the species which bear on their joints 

 wartlike or conical conceptacles, and he divided the genus into tour sections according to 

 the joints: (1) cylindrical with wartlike conceptacula, Euamphiroa\ (2) flatténed, obcordate, 

 subalate, with conical conceptacula, Arthrocardia\ (3) flat and two-edged with conical concep- 

 tacula. Eurytio \ obcordate with acute lobes bearing conceptacles on their superior margin, 

 Cheilosporum. But he adds that this ditïerence alone is nol sufficiënt as a generic character, for 

 one observes transitions between the cylindrical branches of the typical Amphiroa and the 

 flatténed branches of the Arthrocardia section, just as one sees the conceptacles developing 

 gradually on the side of the joints and thus forming the section named Cheilosporum. 



Two years later Zanardini i [844 treated of the Corallines and he was the first to 

 call attention to the anatomical differences between Amphiroa and Corallina. He pointed out 

 that in the genera Jania and Corallina the cells - - which he still called articoli and otricoli — 

 have all the same dimensions, but that this is not the case with Amphiroa, where short cells 

 are intercalated at regular intervals between long ones. This disposition of the cells seems, 

 according to Zanardini, to belong exclusively to the genus Amphiroa and by this internal 

 structure it is distinguished at once trom either Jania or Corallina . By these alternating lavers 

 of long and short cells the transverse zones of Amphiroa are indeed much more marked 

 than in all other genera; but this remark of Zanardini seems to have been overlooked by 

 succeeding authors. 



Harvey 3 ) (1847 — I,s 49.) an d Kützing 4 ) (1849) foliowed Decaisne and characterized the 

 genera by the form of the fruit. Areschoug ( 1 85 1 ) used both the form of the joint and that 

 of the fruit but as Grav') (1867) observed : "Both these characters are good, for they afford 

 the means of dividing the species into very natural groups but in most of these groups there 

 are always species, which combine the characters in such a manner as to make it difficult to 

 determine to which genus they are most nearly allied". Grav created in 1867 the genus 

 Lithotkrix which was sunk into Amphiroa by Anderson 6 ) in 1891. 



Solms-Laubach in his above-quoted monograph of the Corallines of the Gulf of Naples 

 (1881) treated of the genera Amphiroa. Melobesia, Lithothamnion, Lithophyllum and Corallina. 

 He pointed out the development of the fruit of Corallina, which had already been the object 

 of such arduous research by Thuret and Borxet') in 1878, and he also called attention to the 

 many points ot resemblance between Amphiroa and Lithothamnion, which will be spoken of, 

 when the anatomy of Amphiroa is discussed. 



In "Die Natürlichen Pflanzenfamilien" of Engler (1897), the Corallinaceae are treated 



1) Iim A1SNE. Essai sur une Classification des Algues et des polypiers calcifères. Ann. des Sc. Nat. 2" IC ser.. t. XVII, Paris 1S42. 

 1 Revista sulle Corallinee. Atti R. Istituto Veneto vol. III. Serie I. Venezia 1S44. 

 VEY. Nereis australis or algae of the Southern Ocean. London 1S47 — 1849. Phycologia britannica. London 1849 — 1S51. 



ina. 1 Ion 1 ^46 — 1851. 



4) Kützing. Phycologica generalis. Leipzig 1S43. Tabulae phycologicae 1849 — 1869. Species algarum 1S49. 

 1 otkrïx a new genus of Corallirjae. Journ. of lïotany. V, 33. Febr. 1867. 



Zoe vol. II, [891, p. 225. 

 7) Tim 1 et. Études phycologiques. Paris 1S7S. 



