7 6 

 rather long ago has been considered to occur both fossil and recent. Thus Solms-Lai bai b 



6 



remarks in Corall. Monogr. p. [8: "Dass sich Lithothamnion Racemus und ebenso das nachher 

 zu besprechende /.. ramulosum 1 ) seit der Tertiarzeit in unveranderter Weise fortgepfianzt hat, 

 ist mir unzweifelhaft. In den pliocanen Kalken von Syrakus (Latomia dei Cappucini) und von 

 Girerend (rupe Atenea) linden sich Banke, die ausschliesslich aus Nulliporen gebildet sind. Ich 

 habe an ( >rt und Stelle zahlreiche Individuen gesammelt, die sofort als zu den beiden erwahnten 

 Arten orehörig angesprochen wurden und die auch, zu Hause genauer untersucht, auf Dünn- 

 schliflfen vollkommen dvn gleichen Ban wie die recenten, überall an Siciliens Kusten vom Meere 

 ausgeworfenen Pflanzen erkennen Hessen". Also Rothpletz in Foss. Kalkalg. p. 320 mentions 

 this species living as well as fossil. As regards the connection mentioned, Gümbel 2 ) aptly 

 Lrks: "Sie reichen hier (in den Pliocangebilden des Monte Mario), inclem sie in den diluvialen 

 Muschelbanken unzweifelhaft sich fortsetzen, den Gebilden der Jetztzeit die Hand, welche 

 von den Wellen Iosgelöst und an den Strand gespült sich mit Muschelschalen und sonstigem 

 Meeresauswurfe stellenweis zu festem Gestein vereinigen". The species described by him 

 I. c. p. 39 under the name of Lithothamnion pliocaenum from Monte Mario most probably 

 also represents a fossil form of Lithophyllum racemus 3 ), bi addition, the arctic Lithothamnion 

 glaciale is known from several post-glacial sediments both in Norway and Greenland. There 

 are also other species recent and fossil which, when compared more closely, will not unlikely 

 prove to be identic, although it is often impossible to make sure of the relation. Thus in 

 several recent species the reproductive organs are more or less superficial and get dissolved 

 after maturity, not leaving conceptacles which become overgrown by new-formed tissue and, 

 therefore, it can be impossible to decide even to which genus the specimens belong when they 

 are sterile. This is particularly the case in several species within e. g. the genus Lithothamnion, 

 whereas in e. g. the genus Lithophyllum the conceptacles mostly become overgrown, and in the 

 genus Archaeolithothamnion the cavities after the sporangia as well. A similar fact makes its 

 appearance in fossil species too. Therefore, such ones in many cases cannot be determined 

 with any degree of certainty, when they are destitute of overgrown conceptacles. Besides, of fossil 

 species frequently but fragments are in hand, and the structure often affords but an uncertain 

 character. ( )n the other hand, specimens with well developed overgrown conceptacles seem 

 mostly to be recognizable even in fossil sediments, but by no means always. 



The mentioned sections, which Professor K. Martin kindly sent me for examination at 

 the request of Madame A. Weber-van Bosse, are from the island Soëk in Geelvink Bay on 

 the northern coast of New Guinea. Those "121. v. Rosenberg (6) Soëk" contain, among other 

 calcareous algae, several smaller or larger fragments of a plant which in my opinion without 

 any doubt must be ranged with Mastophora melobesioides . Professor A. Wichmann of Utrecht also 

 kindly sent me a number of sections for examination. Among these one is from Mineralogisch- 



1 This speci includes more tlian one ipecii - as suggested by Solms-Laubach himself, at least Lithothamnion 



and Goniolithon Brassii 

 C. VV. G Dii rgenannten Nulliporen und ihre Betheiligung an der Zusamm der Kalkgesteine. 1. — 



Vïathem.-phys. Cl. vol. XI, 1S74, p. 29. 



the cells of Mi pecies described by Gümbel 1. c. cp. Rothpli i/. 1. c. p. 303. 



